Sublingual buprenorphine/naloxone for chronic pain in at-risk patients: development and pilot test of a clinical protocol

A review of trial and real-world data applying elements of a realist approach to identify behavioural mechanisms supporting practitioners to taper opioids

This evidence synthesis applying realist concepts and behavioural science aimed to identify behavioural mechanisms and contexts that facilitate prescribers tapering opioids. We identified relevant opioid‐tapering interventions and services from a 2018 international systematic review and a 2019 England‐wide survey, respectively. Interventions and services were eligible if they provided information about contexts and/or behavioural mechanisms influencing opioid‐tapering success. A stakeholder group (n = 23) generated draft programme theories based around the 14 domains of the Theoretical Domains Framework. We refined these using the trial and service data. From 71 articles and 21 survey responses, 56 and 16 respectively were included, representing primary care, hospital, specialist pain facilities and prison services. We identified 6 programme theories comprising 5 behavioural mechanisms: prescribers' knowledge about how to taper; build prescribers' beliefs about capabilities to initiate tapering discussions and manage psychological consequences of tapering; perceived professional role in tapering; the environmental context enabling referral to specialists; and facilitating positive social influence by aligning patient: prescriber expectations of tapering. No interventions are addressing all 6 mechanisms supportive of tapering. Work is required to operationalise programme theories according to organisational structures and resources. An example operationalisation is combining tapering guidelines with information about local excess opioid problems and endorsing these with organisational branding. Prescribers being given the skills and confidence to initiate tapering discussions by training them in cognitive‐based interventions and incorporating access to psychological and physical support in the patient pathway. Patients being provided with leaflets about the tapering process and informed about the patient pathway.

Buprenorphine initiation strategies for opioid use disorder and pain management: A systematic review

Buprenorphine possesses many unique attributes that make it a practical agent for adults and adolescents with opioid use disorder (OUD) and/or acute or chronic pain. Sublingual buprenorphine has been the standard of care for treating OUD, but its use in pain management is not as clearly defined. Current practice guidelines recommend a period of mild‐to‐moderate withdrawal from opioids before transitioning to buprenorphine due to its ability to displace full agonists from the μ‐opioid receptor. However, this strategy can lead to negative physical and psychological outcomes for patients. Novel initiation strategies suggest that concomitant administration of small doses of buprenorphine with opioids can avoid the unwanted withdrawal associated with buprenorphine initiation. We aim to systematically review the buprenorphine initiation strategies that have emerged in the last decade. Embase, PubMed, and Cochrane Databases were searched for relevant literature. Studies were included if they were published in the English language and described the transition to buprenorphine from opioids. Data were collected from each study and synthesized using descriptive statistics. This review included 7 observational studies, 1 feasibility study, and 39 case reports/series which included 924 patients. The strategies utilized between the literature included traditional initiation (47.9%), microdosing with various buprenorphine formulations (16%), and miscellaneous methods (36.1%). Traditional initiation and microdosing initiation were compared in the data synthesis and analysis; miscellaneous methods were omitted given the high variability between methods. Overall, 95.6% of patients in the traditional initiation group and 96% of patients in the microdosing group successfully rotated to sublingual buprenorphine. Initiation regimens can vary widely depending on patient‐specific factors and buprenorphine formulation. A variety of buprenorphine transition strategies are published in the literature, many of which were effective for patients with OUD, pain, or both.

Efficacy of interventions to reduce long term opioid treatment for chronic non-cancer pain: systematic review and meta-analysis

OBJECTIVE

To review interventions to reduce long term opioid treatment in people with chronic non-cancer pain, considering efficacy on dose reduction and discontinuation, pain, function, quality of life, withdrawal symptoms, substance use, and adverse events.

DESIGN

Systematic review and meta-analysis of randomised controlled trials and non-randomised studies of interventions.

DATA SOURCES

Medline, Embase, PsycINFO, CINAHL, and the Cochrane Library searched from inception to July 2021. Reference lists and previous reviews were also searched and experts were contacted.

ELIGIBILITY CRITERIA FOR STUDY SELECTION

Original research in English. Case reports and cross sectional studies were excluded.

DATA EXTRACTION AND SYNTHESIS

Two authors independently selected studies, extracted data, and used the Cochrane risk-of-bias tools for randomised and non-randomised studies (RoB 2 and ROBINS-I). Authors grouped interventions into five categories (pain self-management, complementary and alternative medicine, pharmacological and biomedical devices and interventions, opioid replacement treatment, and deprescription methods), estimated pooled effects using random effects meta-analytical models, and appraised the certainty of evidence using GRADE (grading of recommendations, assessment, development, and evaluation).

RESULTS

Of 166 studies meeting inclusion criteria, 130 (78%) were considered at critical risk of bias and were excluded from the evidence synthesis. Of the 36 included studies, few had comparable treatment arms and sample sizes were generally small. Consequently, the certainty of the evidence was low or very low for more than 90% (41/44) of GRADE outcomes, including for all non-opioid patient outcomes. Despite these limitations, evidence of moderate certainty indicated that interventions to support prescribers' adherence to guidelines increased the likelihood of patients discontinuing opioid treatment (adjusted odds ratio 1.5, 95% confidence interval 1.0 to 2.1), and that these prescriber interventions as well as pain self-management programmes reduced opioid dose more than controls (intervention v control, mean difference -6.8 mg (standard error 1.6) daily oral morphine equivalent, P<0.001; pain programme v control, -14.31 mg daily oral morphine equivalent, 95% confidence interval -21.57 to -7.05).

CONCLUSIONS

Evidence on the reduction of long term opioid treatment for chronic pain continues to be constrained by poor study methodology. Of particular concern is the lack of evidence relating to possible harms. Agreed standards for designing and reporting studies on the reduction of opioid treatment are urgently needed.

REVIEW REGISTRATION

PROSPERO CRD42020140943.

Anxiety and Fear Avoidance Beliefs and Behavior May Be Significant Risk Factors for Chronic Opioid Analgesic Therapy Reliance for Patients with Chronic Pain-Results from a Preliminary Study

OBJECTIVE

To describe differences between patients with chronic, non-cancer pain (CNCP) who were successfully able to cease full mu agonist chronic opioid analgesic therapy (COAT), and those who exhibited refractory COAT reliance, among those who participated in a multidisciplinary program designed for COAT cessation.

DESIGN

A retrospective review of electronic medical records (EMR) data was organized for preliminary analysis.

SETTING

A multicenter private practice specializing in CNCP, which received patient referrals from the surrounding geographical area of primary and specialty care offices in Northern California.

SUBJECTS

Data from 109 patients with CNCP who participated in a multidisciplinary program to cease COAT between the dates of October 2017 to December 2019 were examined.

METHODS

EMR data, pre-COAT cessation, of oral morphine milligram equivalence (MME) and validated questionnaire responses assessing anxiety and fear-based beliefs and behavior, as well as opioid misuse, were extracted and compared between those who successfully ceased COAT and those who did not.

RESULTS

Patients who were unsuccessful at COAT cessation reported significantly higher Fear Avoidance Beliefs Questionnaire (FAB) scores. No significant differences were found based on incoming MME amounts, Current Opioid Misuse Measure (COMM) or Tampa Scale of Kinesiophobia (TSK) scores. Pain Catastrophizing Scale (PCS) scores showed a split pattern with unclear significance.

CONCLUSIONS

Results suggest that fear avoidance beliefs and behavior, as measured by the FAB, play a significant role in refractory COAT reliance for patients with CNCP.

Evaluation of Buprenorphine Rotation in Patients Receiving Long-term Opioids for Chronic Pain: A Systematic Review

IMPORTANCE

Individuals with chronic pain who use long-term opioid therapy (LTOT) are at risk of opioid use disorder and other harmful outcomes. Rotation to buprenorphine may be considered, but the outcomes of such rotation in this population have not been systematically reviewed.

OBJECTIVE

To synthesize the evidence on rotation to buprenorphine from full μ-opioid receptor agonists among individuals with chronic pain who were receiving LTOT, including the outcomes of precipitated opioid withdrawal, pain intensity, pain interference, treatment success, adverse events or adverse effects, mental health condition, and health care use.

EVIDENCE REVIEW

PubMed, CINAHL, Embase, and PsycInfo were searched from inception through November 3, 2020, for peer-reviewed original English-language research that reported the prespecified outcomes of rotation from prescribed long-term opioids to buprenorphine among individuals with chronic pain. Two independent reviewers extracted data as well as assessed risk of bias and study quality according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Quality of evidence was assessed with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.

FINDINGS

A total of 22 studies were analyzed, of which 5 (22.7%) were randomized clinical trials, 7 (31.8%) were case-control or cohort studies, and 10 (45.5%) were uncontrolled pre-post studies, which involved 1616 unique participants (675 female [41.8%] and 941 male [58.2%] individuals). Six of the 22 studies (27.3%) were primary or secondary analyses of a large randomized clinical trial. Participants had diverse pain and opioid use histories. Rationale for buprenorphine rotation included inadequate analgesia, intolerable adverse effects, risky opioid regimens (eg, high dose and/or sedative coprescriptions), and aberrant opioid use. Most protocols were adapted from protocols for initiating treatment in patients with opioid use disorder and used buccal or sublingual buprenorphine. Very low-quality evidence suggested that buprenorphine rotation was associated with maintained or improved analgesia, with a low risk of precipitating opioid withdrawal. Steady-dose buprenorphine was better tolerated than tapered-dose buprenorphine. Adverse effects were manageable, and severe adverse events were rare. Only 2 studies evaluated mental health outcomes, but none evaluated health care use. Limitations included a high risk of bias in most studies.

CONCLUSIONS AND RELEVANCE

In this systematic review, buprenorphine was associated with reduced chronic pain intensity without precipitating opioid withdrawal in individuals with chronic pain who were receiving LTOT. Future studies are necessary to ascertain the ideal starting dose, formulation, and administration frequency of buprenorphine as well as the best approach to buprenorphine rotation.

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

ABSTRACT

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

Beneficial Effects of Opioid Rotation to Buprenorphine/Naloxone on Opioid Misuse, Craving, Mental Health, and Pain Control in Chronic Non-Cancer Pain Patients with Opioid Use Disorder

Patients with chronic non-cancer pain (CNCP) often use opioids for long periods of time. This may lead to opioid use disorder (OUD) and psychiatric symptoms: mainly depression and anxiety. The current study investigated the effect of buprenorphine/naloxone (BuNa) rotation on opioid misuse, craving, psychiatric symptoms and pain in patients with CNCP and OUD. Forty-three participants with CNCP and OUD were converted from a full mu-receptor agonist opioid (mean morphine equivalent dose: 328.3 mg) to BuNa, in an inpatient setting. Opioid misuse, craving, co-occurring psychiatric symptoms, and pain perception were determined at baseline and after a two-month follow-up, using the following self-report questionnaires: Current Opioid Misuse Measurement (COMM), Visual Analog Scale (VAS-craving and VAS-pain) and Depression, Anxiety and Stress Scale (DASS), respectively. VAS-craving and VAS-pain were also determined immediately after conversion. A total of 37 participants completed the protocol. The mean COMM decreased from 17.1 to 6.7 (F = 36.5; p < 0.000), the mean VAS-craving decreased from 39.3 to 5.3 (−86.6%; F = 26.5, p < 0.000), the mean DASS decreased from 12.1 to 6.6 (F = 56.3, p < 0.000), and the mean VAS-pain decreased from 51.3 to 37.2 (−27.4%, F = 3.3; p = 0.043). Rotation to BuNa in patients with CNCP and OUD was accompanied by reductions in (i) opioid misuse, (ii) opioid craving, (iii) the severity of co-occurring psychiatric symptoms, and (iv) self-reported pain. BuNa as opioid agonist treatment may therefore be a beneficial strategy in CNCP patients with OUD. The limited sample size and the observational nature of this study underline the need for the replication of the current findings in large-scale, controlled studies.

Is Buprenorphine Effective for Chronic Pain? A Systematic Review and Meta-analysis

OBJECTIVE

The objective was to perform a systematic review and meta-analysis of the literature on the effects of buprenorphine on chronic pain outcomes (i.e., patient-reported pain intensity) in patients with and without opioid use disorder (OUD).

DESIGN

Ovid/Medline, PubMed, Embase, and the Cochrane Library were searched for studies that explored the effectiveness (in reducing pain) of buprenorphine treatment for chronic pain patients with and without a history of OUD. Randomized controlled trials and observational studies were included in the review.

METHODS

Two separate searches were conducted to identify buprenorphine trials that included chronic pain patients either with or without OUD. Five studies used validated pain report measures and included a chronic pain population with OUD. Nine studies used validated report measures and included chronic pain patients without OUD. Meta-analysis was performed using the R, version 3.2.2, Metafor package, version 1.9-7.

RESULTS

The meta-analysis revealed that buprenorphine has a beneficial effect on pain intensity overall, with a small mean effect size in patients with comorbid chronic pain and OUD and a moderate- to large-sized effect in chronic pain patients without OUD.

CONCLUSIONS

Our results indicate that buprenorphine is modestly beneficial in reducing pain intensity in patients without OUD. Although informative, these findings should be carefully interpreted due to the small amount of data available and the variation in study designs.

Kappa Opioid Signaling at the Crossroads of Chronic Pain and Opioid Addiction

Pain is complex and is a unique experience for individuals in that no two people will have exactly the same physiological and emotional response to the same noxious stimulus or injury. Pain is composed of two essential processes: a sensory component that allows for discrimination of the intensity and location of a painful stimulus and an emotional component that underlies the affective, motivational, unpleasant, and aversive response to a painful stimulus. Kappa opioid receptor (KOR) activation in the periphery and throughout the neuroaxis modulates both of these components of the pain experience. In this chapter we focus on recent findings that KORs contribute to the emotional, aversive nature of chronic pain, including how expression in the limbic circuitry contributes to anhedonic states and components of opioid misuse disorder. While the primary focus is on preclinical pain models, we also highlight clinical or human research where there is strong evidence for KOR involvement in negative affective states associated with chronic pain and opioid misuse.

Complex Persistent Opioid Dependence with Long-term Opioids: a Gray Area That Needs Definition, Better Understanding, Treatment Guidance, and Policy Changes

The multitude of treatments available for tens of millions of US adults with moderate/severe chronic pain have limited efficacy. Long-term opioid therapy (LTOT) is a widely available option for controlling pain among patients with chronic pain refractory to other treatments. The recent recognition of LTOT inefficacy and complications has led to more frequent opioid tapering, which in turn has revealed its own set of complications. The occurrence of the same set of symptoms-worsening pain, declining function, and clinical instability-in contrasting contexts of LTOT ineffectiveness and opioid tapering has led to increasing recognition of the utility of complex persistent opioid dependence (CPOD), a clinically distinct but biologically similar state compared with opioid use disorder as an explanatory diagnosis/heuristic. Recent guidelines for LTOT tapering have incorporated buprenorphine treatment based on CPOD concepts as a recommended treatment for problems due to opioid tapering with limited supportive evidence. The increasing utilization of buprenorphine for both LTOT ineffectiveness and opioid tapering problems raises the urgent need for a review of the clinical definition, mechanisms, and treatment of CPOD and pertinent policies. In this manuscript, we discuss various issues related to CPOD that requires further clarification through research and policy development.

Benefits and Harms of Long-term Opioid Dose Reduction or Discontinuation in Patients with Chronic Pain: a Rapid Review

BACKGROUND

Many clinicians are reevaluating the use of long-term opioid therapy (LTOT) for chronic pain in response to the opioid crisis and calls from organizations including the Centers for Disease Control & Prevention to limit prescribing of high-dose opioids. However, this practice change is occurring largely in the absence of data regarding patient outcomes. A 2017 systematic review found inconclusive evidence on the impact of LTOT dose reduction and discontinuation on pain severity and function, quality of life, withdrawal symptoms, substance abuse, and adverse effects. This rapid systematic review provides an updated evidence synthesis of patient outcomes following LTOT dose reduction including serious harms such as overdose and suicide.

METHODS

We systematically searched numerous bibliographic databases from January 2017 (the end search date of the 2017 systematic review) through May 2020. One reviewer used prespecified criteria to assess articles for inclusion, evaluate study quality, abstract data, and grade strength of evidence, with a second reviewer checking.

RESULTS

We included 49 studies-1 systematic review, 34 studies included in that systematic review, and 14 new studies. We prioritized evidence synthesis of 19 studies with the most applicability to the Veteran population and outpatient settings. Among these studies, improvements in mean pain scores were common among patients tapering opioids while participating in intensive multimodal pain interventions and mostly unchanged with less intensive or nonspecific co-interventions. Our confidence in these findings is low due to methodological limitations of the studies. Observational data suggests that serious harms such as opioid overdose and suicidal ideation can occur following opioid dose reduction or discontinuation, but the incidence of these harms at the population level is unknown.

DISCUSSION

The net balance of benefits and harms of LTOT dose reduction for patients with chronic pain is unclear. Clinicians should closely monitor patients during the tapering process given the potential for harm.

Randomized clinical trial comparing buprenorphine/naloxone and methadone for the treatment of patients with failed back surgery syndrome and opioid addiction

Opioid analgesic consumption has led to an unprecedented epidemic of overdose death and opioid addiction in the US history. The treatment of chronic pain in patients with opioid addiction who receive prescriptions for opioid medications presents a clinical dilemma. Continuing opioid medication could result in hyperalgesia rendering opioids ineffective and results in iatrogenic therapeutic damage as evidenced by the worsening of addiction. Discontinuing opioid medications could result in severe pain and cravings that often leads the patient to the illicit market. This study compared methadone and buprenorphine/naloxone in patients with failed back surgery syndrome and opioid addiction. Nineteen participants were randomly assigned to methadone or buprenorphine/naloxone and were followed for 6 months. In an intent-to-treat analysis analgesia, craving, functioning, drug use, depression, and treatment retention were assessed monthly. It was planned to enroll 66 patients with failed back surgery syndrome and opioid addiction; however, enrollment was closed early due to suspected abuse of medications. Patients in both treatment conditions exhibited significantly improved 24-hour pain severity with up to 20% reduction of pain severity at the last follow-up (p < .05). However, patients receiving methadone reported significantly reduced current pain severity, whereas patients receiving buprenorphine/naloxone did not. Patients reported significantly improved functioning, fewer cravings, less opioid use, and depression (p < .05) across the treatment conditions. When given a choice between methadone and buprenorphine/naloxone, buprenorphine/naloxone is recommended due to its superior safety profile. Treatment with either needs to be monitored closely.

Hospital Opioid Requirements Following Continuation Versus Discontinuation of Buprenorphine for Addiction - A Retrospective Cohort Study

Evidence guiding inpatient management of buprenorphine is lacking-this retrospective cohort study evaluated the clinical impact of hospital continuation versus discontinuation of buprenorphine at an academic medical center. The primary outcome was inpatient oral morphine equivalents (OME). Secondary outcomes included patient pain levels, functional assessment, and hospital length of stay. One hundred thirty-one patients (74 continued buprenorphine, 57 discontinued) were included in the analysis. Median OME were significantly lower among patients continued on buprenorphine versus discontinued (11 mg vs 103 mg, p < 0.001), as was maximum 24-hour opioid utilization (60 mg vs 240 mg, p < 0.001) and 24-hour pre-discharge utilization (10 mg vs 128 mg, p < 0.001). Median pain levels were similar between groups at the time of admission (8 in each group, p = 0.48), discharge (7 in each group, p = 0.26), and over the first 7 days of hospitalization (7 vs 8, p = 0.08). Hospital length of stay was similar between groups (5 days in each group, p > 0.99). Failure to reinitiate buprenorphine occurred in 31/57 patients (54.4%) in the discontinuation group. Hospital buprenorphine continuation is associated with reduced opioid requirements, while not significantly impacting pain levels, functionality, or length of admission. Failure to reinitiate buprenorphine was common and may have negative implications for addiction treatment.

Does Opioid Tapering in Chronic Pain Patients Result in Improved Pain or Same Pain vs Increased Pain at Taper Completion? A Structured Evidence-Based Systematic Review

Objective

To support or refute the hypothesis that opioid tapering in chronic pain patients (CPPs) improves pain or maintains the same pain level by taper completion but does not increase pain.

Methods

Of 364 references, 20 fulfilled inclusion/exclusion criteria. These studies were type 3 and 4 (not controlled) but reported pre/post-taper pain levels. Characteristics of the studies were abstracted into tabular form for numerical analysis. Studies were rated independently by two reviewers for quality. The percentage of studies supporting the above hypothesis was determined.

Results

No studies had a rejection quality score. Combining all studies, 2,109 CPPs were tapered. Eighty percent of the studies reported that by taper completion pain had improved. Of these, 81.25% demonstrated this statistically. In 15% of the studies, pain was the same by taper completion. One study reported that by taper completion, 97% of the CPPs had improved or the same pain, but CPPs had worse pain in 3%. As such, 100% of the studies supported the hypothesis. Applying the Agency for Health Care Policy and Research Levels of Evidence Guidelines to this result produced an A consistency rating.

Conclusions

There is consistent type 3 and 4 study evidence that opioid tapering in CPPs reduces pain or maintains the same level of pain. However, these studies represented lower levels of evidence and were not designed to test the hypothesis, with the evidence being marginal in quality with large amounts of missing data. These results then primarily reveal the need for controlled studies (type 2) to address this hypothesis.

Web-Based Cognitive Behavior Therapy for Chronic Pain Patients with Aberrant Drug-Related Behavior: Outcomes from a Randomized Controlled Trial

Objective

There is high unmet need for effective behavioral treatments for chronic pain patients at risk for or with demonstrated histories of opioid misuse. Despite growing evidence supporting technology-based delivery of self-management interventions for chronic pain, very few such programs target co-occurring chronic pain and aberrant drug-related behavior. This randomized controlled trial evaluated the effectiveness of a novel, web-based self-management intervention, grounded in cognitive behavior therapy, for chronic pain patients with aberrant drug-related behavior.

Methods

Opioid-treated chronic pain patients at a specialty pain practice who screened positive for aberrant drug-related behavior (N = 110) were randomized to receive treatment as usual plus the web-based program or treatment as usual alone. The primary outcomes of pain severity, pain interference, and aberrant drug-related behavior, and the secondary outcomes of pain catastrophizing and pain-related emergency department visits, were assessed during the 12-week intervention and at one and three months postintervention.

Results

Patients assigned to use the web-based program reported significantly greater reductions in aberrant drug-related behavior, pain catastrophizing, and pain-related emergency department visits-but not pain severity or pain interference-relative to those assigned to treatment as usual. The positive outcomes were observed during the 12-week intervention and for three months postintervention.

Conclusions

A web-based self-management program, when delivered in conjunction with standard specialty pain treatment, was effective in reducing chronic pain patients' aberrant drug-related behavior, pain catastrophizing, and emergency department visits for pain. Technology-based self-management tools may be a promising therapeutic approach for the vulnerable group of chronic pain patients who have problems managing their opioid medication.

Treating Chronic Pain: An Overview of Clinical Studies Centered on the Buprenorphine Option

The buprenorphine receptor binding profile is unique in that it binds to all three major opioid receptors (mu, kappa, delta), and also binds to the orphan-like receptor, the receptor for orphanin FQ/nociceptin, with lower affinity. Within the mu receptor group, buprenorphine analgesia in rodents is dependent on the recently discovered arylepoxamide receptor target in brain, which involves a truncated 6-transmembrane mu receptor gene protein, distinguishing itself from morphine and most other mu opioids. Although originally designed as an analgesic, buprenorphine has mainly been used for opioid maintenance therapy and only now is increasingly recognized as an effective analgesic with an improved therapeutic index relative to certain potent opioids. Albeit a second-, third-, or fourth-line analgesic, buprenorphine is a reasonable choice in certain clinical situations. Transdermal patches and buccal film formulations are now commercially available as analgesics. This review discusses buprenorphine pharmacodynamics and pharmacokinetics, use in certain populations, and provides a synopsis of systematic reviews and randomized analgesic trials. We briefly discuss postoperative management in patients receiving buprenorphine maintenance therapy, opioid equivalence to buprenorphine, rotations to buprenorphine from other opioids, and clinical relevance of buprenorphine-related QTc interval changes.

Volatility and change in chronic pain severity predict outcomes of treatment for prescription opioid addiction

BACKGROUND AND AIMS

Buprenorphine-naloxone (BUP-NLX) can be used to manage prescription opioid addiction among persons with chronic pain, but post-treatment relapse is common and difficult to predict. This study estimated whether changes in pain over time and pain volatility during BUP-NLX maintenance would predict opioid use during the taper BUP-NLX taper.

DESIGN

Secondary analysis of a multi-site clinical trial for prescription opioid addiction, using data obtained during a 12-week BUP-NLX stabilization and 4-week BUP-NLX taper.

SETTING

Community clinics affiliated with a national clinical trials network in 10 US cities.

PARTICIPANTS

Subjects with chronic pain who entered the BUP-NLX taper phase (n = 125) with enrollment occurring from June 2006 to July 2009 (52% male, 88% Caucasian, 31% married).

MEASUREMENTS

Outcomes were weekly biologically verified and self-reported opioid use from the 4-week taper phase. Predictors were estimates of baseline severity, rate of change and volatility in pain from weekly self-reports during the 12-week maintenance phase.

FINDINGS

Controlling for baseline pain and treatment condition, increased pain [odds ratio (OR) = 2.38, P = 0.02] and greater pain volatility (OR = 2.43, P = 0.04) predicted greater odds of positive opioid urine screen during BUP-NLX taper. Increased pain (IRR = 1.40, P = 0.04) and greater pain volatility [incidence-rate ratio (IRR) = 1.66, P = 0.009] also predicted greater frequency of self-reported opioid use.

CONCLUSIONS

Adults with chronic pain receiving out-patient treatment with buprenorphine-naloxone (BUP-NLX) for prescription opioid addiction have an elevated risk for opioid use when tapering off maintenance treatment. Those with relative persistence in pain over time and greater volatility in pain during treatment are less likely to sustain abstinence during BUP-NLX taper.

A review: Fentanyl and non-pharmaceutical fentanyls

BACKGROUND

Fentanyl and non-pharmaceutical fentanyls (NPFs) have been responsible for numerous outbreaks of overdoses all over the United States since the 1970s. However, there has been a growing concern in recent years that NPFs are contributing to an alarming rise in the number of opioid-related overdoses.

METHODS

The authors conducted a narrative review of the published and grey literature on fentanyl and NPFs in PubMed, Google Scholar, and Google using the following search terms: "fentanyl", "non-pharmaceutical fentanyl", "fentanyl analogs", "fentanyl laced heroin" and "fentanyl overdose". References from relevant publications and grey literature were also reviewed to identify additional citations for inclusion.

RESULTS

The article reviews the emergence and misuse of fentanyl and NPFs, their clinical pharmacology, and the clinical management and prevention of fentanyl-related overdoses.

CONCLUSIONS

Fentanyl and NPFs may be contributing to the recent rise in overdose deaths in the United States. There is an urgent need to educate clinicians, researchers, and patients about this public health threat.

Management of patients with issues related to opioid safety, efficacy and/or misuse: a case series from an integrated, interdisciplinary clinic

Background

Patients, providers, communities and health systems have struggled to achieve balance between access to opioid treatment for chronic pain and its potential harmful consequences: especially misuse, addiction and overdose. We developed an interdisciplinary clinic embedded within primary care (the Opioid Reassessment Clinic—ORC) with the goal of improving the quality of care of patients with co-occurring chronic pain and issues related to opioid safety, efficacy and/or misuse.

Case descriptions

We present three cases referred to the ORC that highlight complex clinical scenarios related to assessment and treatment of patients with chronic pain and issues related to opioid safety, efficacy and misuse.

Discussion and evaluation

In the context of the three cases, with respect to assessment, we discuss: making the diagnosis of opioid use disorder; allowing the patient space to endorse lack of efficacy; identification of co-occurring hazardous alcohol use; and recognizing barriers to multimodal pain care. With respect to treatment, we discuss: making a change in treatment with which the patient may not agree; effectiveness of buprenorphine/naloxone for the treatment of chronic pain; responding to low efficacy; and making continued opioid therapy contingent on engagement with substance abuse treatment.

Conclusions

The core components of our approach—biopsychosocial assessment and multimodal treatment planning with an emphasis on promoting functional goals and safety using clear communication and a patient-centered stance—should guide providers in the management of similar clinical scenarios. More evidence is needed to definitively guide specific interventions and points of clinical equipoise.

Characterizing pain and associated coping strategies in methadone and buprenorphine-maintained patients

BACKGROUND

Chronic pain is common among patients receiving opioid maintenance treatment (OMT) for opioid use disorder. To aid development of treatment recommendations for coexisting pain and opioid use disorder, it is necessary to characterize pain treatment needs and assess whether needs differ as a function of OMT medication.

METHODS

A point-prevalence survey assessing pain and engagement in coping strategies was administered to 179 methadone and buprenorphine-maintained patients.

RESULTS

Forty-two percent of participants were categorized as having chronic pain. Methadone patients had greater severity of pain relative to buprenorphine patients, though both groups reported high levels of interference with daily activities, and participants with pain attended the emergency room more frequently relative to participants without pain. Only 2 coping strategies were being utilized by more than 50% of participants (over-the-counter medication, prayer).

CONCLUSIONS

Results indicate that pain among OMT patients is common, severe, and of significant impairment. Methadone patients reported greater severity pain, particularly worse pain in the past 24h, though interference from pain in daily activities did not vary as a function of OMT. Most participants with pain were utilizing few evidenced-based pain coping strategies. Increasing OMT patient access to additional pain treatment strategies is an opportunity for immediate intervention, and similarities across OMT type suggest interventions do not need to be customized to methadone vs. buprenorphine patients.

Pain volatility and prescription opioid addiction treatment outcomes in patients with chronic pain

The combination of prescription opioid dependence and chronic pain is increasingly prevalent and hazardous to public health. Variability in pain may explain poor prescription opioid addiction treatment outcomes in persons with chronic pain. This study examined pain trajectories and pain volatility in patients with chronic pain receiving treatment for prescription opioid addiction. We conducted secondary analyses of adults with chronic pain (n = 149) who received buprenorphine/naloxone (BUP/NLX) and counseling for 12 weeks in an outpatient, multisite clinical trial. Good treatment outcome was defined as urine-verified abstinence from opioids at treatment endpoint (Week 12) and during at least 2 of the previous 3 weeks. Pain severity significantly declined over time during treatment (b = -0.36, p < .001). Patients with greater pain volatility were less likely to have a good treatment outcome (odds ratio = 0.55, p < .05), controlling for baseline pain severity and rate of change in pain over time. A 1 standard deviation increase in pain volatility was associated with a 44% reduction in the probability of endpoint abstinence. The significant reduction in subjective pain during treatment provides observational support for the analgesic effects of BUP/NLX in patients with chronic pain and opioid dependence. Patients with greater volatility in subjective pain during treatment have increased risk of returning to opioid use by the conclusion of an intensive treatment with BUP/NLX and counseling. Future research should examine underlying mechanisms of pain volatility and identify related therapeutic targets to optimize interventions for prescription opioid addiction and co-occurring chronic pain.

An observational study of buprenorphine treatment of the prescription opioid dependent pain patient

BACKGROUND AND OBJECTIVES

In some countries, particularly the United States and Canada, there has been a growing problem of opioid dependence associated with the treatment of chronic pain. Controversy exists regarding the efficacy and safety of opioid therapy, particularly in high doses for extended periods of time. This study reports on the outcome of chronic pain patients treated with buprenorphine in an outpatient psychiatric consultation clinic.

METHODS

Forty three consecutive outpatient clinic chronic pain patients with a DSM-IV diagnosis of opioid dependence and treated with buprenorphine during a 3-year period were monitored for follow-up periods of up to 5 years. All subjects were dependent on drugs prescribed for pain and were divided into two groups: those who had a history of abuse of alcohol or drugs and those who did not Historical, physical, demographic, and outcome data were collected.

RESULTS

The majority of patients were male, not working, and between the ages of 45-60. Follow-up revealed that treatment with buprenorphine was effective. Most patients had improved pain with treatment of the opioid dependence. There were no differences between those with or without a history of substance abuse.

DISCUSSION AND CONCLUSIONS

Patients often improved with much less preoccupation with pain, expressing great satisfaction with buprenorphine treatment.

SCIENTIFIC SIGNIFICANCE

Buprenorphine is an effective tool when treating the opioid-dependent chronic pain patient.

Sublingual buprenorphine as an analgesic in chronic pain: a systematic review

OBJECTIVE

There is growing interest in the use of sublingual buprenorphine for the treatment of chronic pain due to the unique pharmacology of buprenorphine, widespread use of the transdermal buprenorphine patch for chronic pain, and recent availability of sublingual buprenorphine tablets for the treatment of opioid dependence. The aim of this systematic review was to evaluate the evidence from clinical trials that have assessed the effectiveness of sublingual buprenorphine for chronic pain analgesia.

METHODS

Electronic searches of MEDLINE, Embase, CINAHL, Web of Science, and the Cochrane Database of Systematic Reviews were used to identify clinical trials of sublingual buprenorphine for the treatment of chronic pain.

RESULTS

Ten trials involving 1,190 patients were included in the review. Due to heterogeneity of studies, pooling of the results and meta-analysis were not possible. All studies reported that sublingual buprenorphine demonstrated some effectiveness as a chronic pain analgesic. The majority of studies were observational and of low quality.

CONCLUSIONS

Preliminary trials suggest a plausible role; however, due to a paucity of high-quality trials, the current evidence is insufficient to determine the effectiveness of sublingual buprenorphine for the treatment of chronic pain. Rigorous further trials are warranted.

The relationship between primary prescription opioid and buprenorphine-naloxone induction outcomes in a prescription opioid dependent sample

BACKGROUND AND OBJECTIVES

This analysis aims to: (1) compare induction experiences among participants who self-reported using one of the four most commonly reported POs, and (2) examine factors associated with difficult bup-nx induction. Our hypothesis, based on previous research and current guidelines, is that those on longer-acting opioids will have experienced more difficult inductions.

METHODS

The Prescription Opioid Addiction Treatment Study (POATS) was a multi-site, randomized clinical trial, using a two-phase adaptive treatment research design. This analysis examines bup-nx induction of participants who self-reported primary PO use of methadone, ER-oxycodone, IR-oxycodone, and hydrocodone (n = 69). Analyses examined characteristics associated with difficult induction, defined as increased withdrawal symptoms measured by the Clinical Opiate Withdrawal Scale (COWS) after the first bup-nx dose with higher scores denoting greater withdrawal symptoms/severity.

RESULTS

Contrary to our hypothesis, difficult induction experiences did not differ by primary PO type. Those who experienced a post-induction increase in COWS score had lower pre-dose COWS scores compared to those who did not experience a post-induction increase in COWS score (10.09 vs. 12.77, t(624) = -13.56, p < .001). Demographics characteristics, depression, and pain history did not predict a difficult induction.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

Difficult bup-nx inductions were not associated with participants' primary PO. Severity of withdrawal, measured with the COWS, was an important variable, reminding clinicians that bup-nx should not be commenced prior to evidence of moderate opioid withdrawal. These findings add to the evidence that with careful procedures, bup-nx can used with few difficulties in PO-dependent patients. (Am J Addict 2014;23:343-348).

Implementation of a collaborative care management program with buprenorphine in primary care: a comparison between opioid-dependent patients and patients with chronic pain using opioids nonmedically

OBJECTIVE

To implement a collaborative care management program with buprenorphine in a primary care clinic.

DESIGN

Prospective observational study.

SETTING

A busy urban academic primary care clinic affiliated with a tertiary care hospital.

PARTICIPANTS

Opioid-dependent patients or patients with chronic pain using opioids nonmedically were recruited for the study. A total of 45 participants enrolled.

INTERVENTIONS

Patients were treated with buprenorphine and managed by a supervising psychiatrist, pharmacist care manager, and health coaches. The care manager conducted buprenorphine inductions and all follow-up visits. Health coaches offered telephonic support. The psychiatrist supervised both the care manager and health coaches.

MAIN OUTCOME MEASURES

Primary outcomes were treatment retention at 6 months, and change in the proportion of aberrant toxicology results and opioid craving scores from baseline to 6 months. After data collection, clinical outcomes were compared between opioid-dependent patients and patients with chronic pain using opioids nonmedically. Overall, 55.0 percent of participants (25/45) remained in treatment at 6 months. Primary care physicians (PCPs)' attitudes about opioid dependence treatment were surveyed at baseline and at 18 months.

RESULTS

Forty-three patients (95.6 percent) accepted treatment and 25 (55.0 percent) remained in treatment at 6 months. The proportion of aberrant urine toxicology results decreased significantly from baseline to 6 months (p < 0.01). Craving scores significantly decreased from baseline to 6 months (p < 0.01). Opioid-dependent patients, as opposed to patients with chronic pain using opioids nonmedically, were significantly more likely to complete 6 months of treatment (p < 0.05). PCPs' confidence in treating opioid dependence in primary care increased significantly from baseline to 18 months postimplementation (p < 0.01).

CONCLUSION

Collaborative care management for opioid dependence with buprenorphine may be feasible in a primary care clinic. More research is needed to understand the role of buprenorphine in managing patients with chronic pain using opioids nonmedically.

Endogenous opiates and behavior: 2012

This paper is the thirty-fifth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2012 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).

Opioid antagonists for pain

INTRODUCTION

Opioid receptor antagonists are well known for their ability to attenuate or reverse the effects of opioid agonists. This property has made them useful in mitigating opioid side effects, overdose and abuse. Paradoxically, opioid antagonists have been reported to produce analgesia or enhance analgesia of opioid agonists. The authors review the current state of the clinical use of opioid antagonists as analgesics.

AREAS COVERED

Published clinical trials, case reports and other sources were reviewed to determine the effectiveness and safety of opioid antagonists for use in relieving pain. The results are summarized. Postulated mechanisms for how opioid antagonists might exert an analgesic effect are also briefly summarized.

EXPERT OPINION

Since the comprehensive review by Leavitt in 2009, few new studies on the use of opioid antagonists for pain have been published. The few clinical trials generally consist of small populations. However, there does appear to be a trend of effectiveness of low doses (higher doses antagonize opioid agonist effects). How opioid antagonists can elicit an analgesic effect is still unclear, but a number of possibilities have been suggested. Although the data do not yet support recommendation of widespread application of this off-label use of opioid antagonists, further study appears worthwhile.

Metabolic and toxicological considerations of the opioid replacement therapy and analgesic drugs: methadone and buprenorphine

INTRODUCTION

Methadone and buprenorphine are maintenance replacement therapies for opioid dependence; they are also used for pain management. Methadone and buprenorphine (to a lesser extent) have seen sharp increases in mortality associated with their use. They have distinct routes of metabolism (mostly cytochrome P450 dependent), and distinct pharmacologic activity of metabolites. As such, metabolism may play a role in differences in their toxicity.

AREAS COVERED

This article reviews peer-reviewed literature obtained from PubMed searches and literature referenced within. The review considers first an overview of drug use and mortality over the past decade. It then provides extensive detail on the in vitro and in vivo human metabolism of methadone and buprenorphine. Using both human and experimental animal studies it then presents the pharmacodynamic activity of parent drug and metabolites at the mu-opioid receptor, as P-glycoprotein substrates and plasma/brain concentration ratios, and activity at the hERG K(+) channel. Lessons learned from drug interaction studies in humans are then examined in an attempt to bring together the combined information.

EXPERT OPINION

The use and misuse of these drugs contributes to the epidemic in opioid-associated mortalities. A better understanding of metabolism-, transport- and co-medication-induced changes will contribute to their safer use.