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

Managing Opioid Withdrawal Symptoms During the Fentanyl Crisis: A Review

Illicitly manufactured fentanyl (IMF) is a significant contributor to the increasing rates of overdose-related deaths. Its high potency and lipophilicity can complicate opioid withdrawal syndromes (OWS) and the subsequent management of opioid use disorder (OUD). This scoping review aimed to collate the current OWS management of study populations seeking treatment for OWS and/or OUD directly from an unregulated opioid supply, such as IMF. Therefore, the focus was on therapeutic interventions published between January 2010 and November 2023, overlapping with the period of increasing IMF exposure. A health science librarian conducted a systematic search on November 13, 2023. A total of 426 studies were screened, and 173 studies were reviewed at the full-text level. Forty-nine studies met the inclusion criteria. Buprenorphine and naltrexone were included in most studies with the goal of transitioning to a long-acting injectable version. Various augmenting agents were tested (buspirone, memantine, suvorexant, gabapentin, and pregabalin); however, the liberal use of adjunctive medication and shortened timelines to initiation had the most consistently positive results. Outside of FDA-approved medications for OUD, lofexidine, gabapentin, and suvorexant have limited evidence for augmenting opioid agonist initiation. Trials often have low retention rates, particularly when opioid agonist washout is required. Neurostimulation strategies were promising; however, they were developed and studied early. Precipitated withdrawal is a concern; however, the rates were low and adequately mitigated or managed with low- or high-dose buprenorphine induction. Maintenance treatment continues to be superior to detoxification without continued management. Shorter induction protocols allow patients to initiate evidence-based treatment more quickly, reducing the use of illicit or non-prescribed substances.

Implementation of a Medication for Addiction Treatment (MAT) and Linkage Program by Leveraging Community Partnerships and Medical Toxicology Expertise

INTRODUCTION

Implementing a hospital medication for addiction treatment (MAT) and a linkage program can improve care for patients with substance use disorder (SUD); however, lack of hospital funding and brick and mortar SUD resources are potential barriers to feasibility.

METHODS

This study assesses the feasibility of implementation of a SUD linkage program. Components of the program include a county-funded hospital opioid support team (HOST), a hospital-employed addiction recovery specialist (ARS), and a medical toxicology MAT induction service and maintenance program. Data for linkage by HOST, ARS, and MAT program were tracked from July 2018 to December 2019.

RESULTS

From July 2018 through December 2019, 1834 patients were linked to treatment: 1536 by HOST and 298 by the ARS. The most common disposition categories for patients linked by HOST were 16.73% to medically monitored detoxification, 9.38% to intensive outpatient, and 8.59% to short-term residential treatment. Among patients linked by the ARS, 65.66% were linked to outpatient treatment and 9.43% were linked directly to inpatient treatment. A total of 223 patients managed by the ARS were started on MAT by medical toxicology and linked to outpatient MAT clinic: 72.68% on buprenorphine/naloxone, 24.59% on naltrexone, 1.09% buprenorphine, and 0.55% acamprosate.

CONCLUSION

Implementing a MAT and linkage program in the ED and hospital setting was feasible. Leveraging medical toxicology expertise as well as community and funding partnerships was crucial to successful implementation.

Dose-dependent naloxone-induced morphine withdrawal symptoms in opioid-dependent males-a double-blinded, randomized study

Aims

Oral opioid preparations combined with naloxone are intended to induce a transient acute withdrawal syndrome to avoid intravenous misuse. This trial aimed to establish an appropriate morphine–naloxone dose ratio for an abuse‐deterrent oral opioid formulation.

Methods

In a randomized, double‐blinded, 2 × 2 cross‐over trial, 43 patients with opioid use disorder were challenged with intravenous morphine HCl Ph.Eur. (75 mg; [morphine mono]) or morphine HCl Ph.Eur. and naloxone HCl Ph.Eur. at ratios of 100:1 (75 mg: 0.75 mg; [morphine–naloxone 100:1]) or 200:1 (75 mg: 0.375 mg; [morphine–naloxone 200:1]). Acute naloxone‐induced opioid withdrawal was evaluated using subjective (Short Opiate Withdrawal Scale–German [SOWS‐G]) and observer‐rated (Objective Opiate Withdrawal Scale [OOWS], Wang scale) questionnaires, and physiological parameters. For statistical analysis, the area under the curve between baseline and 20 minutes after drug administration of the outcome variables was calculated.

Results

Intravenous morphine–naloxone caused rapid withdrawal symptoms. Coadministration of naloxone dose‐dependently (morphine–naloxone 100:1 > morphine–naloxone 200:1) increased SOWS‐G, OOWS and Wang Scale area under the curve when compared to morphine mono, respectively (all P < .0001). A similar response was detectable for changes of pupil diameter. Blood pressure and respiratory rate changed heterogeneously, and heart rate was unaltered by morphine without or with naloxone.

Conclusion

Morphine–naloxone 100:1 effectively suppresses the pleasurable effects of intravenous morphine and results in an aversive withdrawal reaction. A lower naloxone concentration as used in morphine–naloxone 200:1 does not appear to be appropriate to prevent intravenous morphine misuse.

Dissatisfaction with opioid maintenance treatment partly explains reported side effects of medications

BACKGROUND

Drop-out is a core problem in opioid maintenance treatment (OMT), but patients' reactions to and acceptance of the various OMT medications are insufficiently investigated. In Norway, there has been vocal patient resistance to the newest medication, buprenorphine-naloxone (BNX), and complaints have focused on the side effect profile. There has been no comparison of patient satisfaction and side effects of the three most common OMT medications.

AIM

To compare patient satisfaction with OMT and side effects of BNX, buprenorphine monopreparate (BUP), and methadone (MET) as reported by patients.

METHODS

Data were drawn from a national peer-to-peer survey developed by a patient advocacy group. The survey engaged more than 1000 OMT patients, corresponding to one seventh of OMT patients in Norway. The associations between side effects, treatment satisfaction, and patient characteristics were tested in multinomial logistic regressions.

RESULTS

High patient satisfaction with OMT overall was reported despite lower satisfaction with medication itself and widely prevalent side effects. Among each medication group, dissatisfaction with medications or OMT in general along with poor health status increased the relative risk ratio of reporting the heaviest side effect burden. MET users reported the highest side effect burden and BNX users the lightest, but BNX users were more dissatisfied with their medication.

CONCLUSIONS

Side effects are a concern for nearly all OMT patients, and they do not appear to accumulate with age or length of treatment. BNX users' dissatisfaction with their medication is of particular concern, and expectations and preferences of medication may be influencing their dissatisfaction.

Opioid substitution treatment and heroin dependent adolescents: reductions in heroin use and treatment retention over twelve months

BACKGROUND

Opioid dependence is a major health concern across the world and does also occur in adolescents. While opioid substitution treatment (OST) has been thoroughly evaluated in adult populations, very few studies have examined its use in adolescents. There are concerns that OST is underutilised in adolescents with heroin dependence. We sought to measure changes in drug use among adolescents receiving OST and also to examine treatment attrition during the first 12 months of this treatment.

METHODS

We included all heroin dependent patients aged under 18.5 years commencing OST at one outpatient multidisciplinary adolescent addiction treatment service in Dublin, Ireland. Psycho-social needs were also addressed during treatment. Drug use was monitored by twice weekly urine drugs screens (UDS). Change in the proportion of UDS negative for heroin was examined using the Wilcoxon signed rank test. Attrition was explored via a Cox Regression multivariate analysis.

RESULTS

OST was commenced by 120 patients (51% female and mean age 17.3 years). Among the 39 patients who persisted with OST until month 12, heroin abstinence was 21% (95% confidence interval [CI] = 9-36%) at month three and it was 46% (95% CI = 30-63%) at month 12. Heroin use declined significantly from baseline to month three (p < 0.001) and from month three to month 12 (p = 0.01). Use of other drugs did not change significantly. People using cocaine during month 12 were more likely to be also using heroin (p = 0.02). Unplanned exit occurred in 25% patients by 120 days. The independent predictors of attrition were having children, single parent family of origin, not being in an intimate relationship with another heroin user and evidence of cocaine use just before treatment entry.

CONCLUSIONS

We found that heroin dependent adolescent patients achieved significant reductions in heroin use within three months of starting OST and this improved further after a year of treatment, about half being heroin abstinent at that stage. Patient drop out from treatment remains a challenge, as it is in adults. Cocaine use before and during treatment may be a negative prognostic factor.

Characteristics and experiences of buprenorphine-naloxone use among polysubstance users

BACKGROUND

With a rise in overdoses and medical emergencies related to opioids, buprenorphine-naloxone (bup-nx) is seen as a preferred treatment for opioid dependence. However, the research examining experiences with bup-nx among polysubstance users who may or may not be opioid dependent has been limited.

OBJECTIVES

The purpose of the study was to examine use, characteristics of users, and experiences of bup-nx use among polysubstance users entering drug-free recovery programs.

METHODS

This study examined secondary data on 896 opioid or opiate user individuals (53.4% male) collected by drug-free, self-help-based residential recovery centers during intake.

RESULTS

One-quarter of users said bup-nx helped them with their substance use while 75% of bup-nx users reported that bup-nx either had no effect or a negative effect on their drug problems. Of the very few (4%-7%) obtaining bup-nx solely through a prescription, over 90% reported relief from withdrawal. However, over 80% of those who obtained bup-nx through illicit means reported using bup-nx until their preferred drug could be obtained and used it for its euphoriant effect. Three groups of opioid users were created including one group with no bup-nx use, one with lifetime but not recent bup-nx use, and one with recent (past 6 month) use. There were differences in substance use patterns and characteristics of bup-nx experiences between the different groups.

CONCLUSIONS

Results suggest that the views of bup-nx by individuals in drug-free recovery centers are varied, with many seeing bup-nx as not unlike other opioids while others report bup-nx as self-medication.

Pharmacogenomics-guided policy in opioid use disorder (OUD) management: An ethnically-diverse case-based approach

INTRODUCTION

Opioid use disorder (OUD) is characterized by a problematic pattern of opioid use leading to clinically-significant impairment or distress. Opioid agonist treatment is an integral component of OUD management, and buprenorphine is often utilized in OUD management due to strong clinical evidence for efficacy. However, interindividual genetic differences in buprenorphine metabolism may result in variable treatment response, leaving some patients undertreated and at increased risk for relapse. Clinical pharmacogenomics studies the effect that inherited genetic variations have on drug response. Our objective is to demonstrate the impact of pharmacogenetic testing on OUD management outcomes.

METHODS

We analyzed a patient who reported discomfort at daily buprenorphine dose of 24 mg, which was a mandated daily maximum by the pharmacy benefits manager. Regular urine screenings were conducted to detect the presence of unauthorized substances, and pharmacogenetic testing was used to determine the appropriate dose of buprenorphine for OUD management.

RESULTS

At the 24 mg buprenorphine daily dose, the patient had multiple relapses with unauthorized substances. Pharmacogenetic testing revealed that the patient exhibited a cytochrome P450 3A4 ultrarapid metabolizer phenotype, which necessitated a higher than recommended daily dose of buprenorphine (32 mg) for adequate OUD management. The patient exhibited a reduction in the number of relapses on the pharmacogenetic-based dose recommendation compared to standard dosing.

CONCLUSION

Pharmacogenomic testing as clinical decision support helped to individualize OUD management. Collaboration by key stakeholders is essential to establishing pharmacogenetic testing as standard of care in OUD management.

Treatment Outcome Comparison Between Telepsychiatry and Face-to-face Buprenorphine Medication-assisted Treatment for Opioid Use Disorder: A 2-Year Retrospective Data Analysis

OBJECTIVES

To retrospectively review clinic records to assess the difference between face-to-face and telepsychiatry buprenorphine medication-assisted treatment (MAT) programs for the treatment of opioid use disorder on 3 outcomes: additional substance use, average time to achieve 30 and 90 consecutive days of abstinence, and treatment retention rates at 90 and 365 days.

METHODS

Medical records of patients (N = 100) who were participating in telepsychiatry and in face-to-face group-based outpatient buprenorphine MAT programs were reviewed and assessed using descriptive statistical analysis.

RESULTS

In comparison with the telepsychiatry MAT group, the face-to-face MAT group showed no significant difference in terms of additional substance use, time to 30 days (P = 0.09) and 90 days of abstinence (P = 0.22), or retention rates at 90 and 365 days (P = 0.99).

CONCLUSIONS

We did not find any significant statistical difference between telepsychiatry buprenorphine MAT intervention through videoconference and face-to-face MAT treatment in our Comprehensive Opioid Addiction Treatment model for individuals diagnosed with opioid use disorder in terms of additional substance use, average time to 30 and 90 days of abstinence, and treatment retention rates.

Very early disengagement and subsequent re-engagement in primary care Office Based Opioid Treatment (OBOT) with buprenorphine

INTRODUCTION

Patients with opioid use disorder often require multiple treatment attempts before achieving stable recovery. Rates of disengagement from buprenorphine are highest in the first month of treatment and termination of buprenorphine therapy results in return to use rates as high as 90%. To better characterize these at-risk patients, this study aims to describe: 1) the frequency and characteristics of patients with very early disengagement (≤1month) from Office Based Opioid Treatment (OBOT) with buprenorphine and 2) the frequency and characteristics of patients who re-engage in care at this same OBOT clinic within 2years, among the subset of very early disengagers.

METHODS

This is a retrospective cohort study of adult patients enrolled in a large urban OBOT program. Descriptive statistics were used to characterize the sample and the proportion of patients with very early (≤1month) disengagement and their re-engagement. Multivariable logistic regression models were used to identify patient characteristics associated with the outcomes of very early disengagement and re-engagement. Potential predictors included: sex, age, race/ethnicity, education, employment, opioid use history, prior substance use treatments, urine drug testing, and psychiatric diagnoses.

RESULTS

Overall, very early disengagement was unusual, with only 8.4% (104/1234) of patients disengaging within the first month. Among the subset of very early disengagers with 2years of follow-up, the proportion who re-engaged with this OBOT program in the subsequent 2years was 11.9% (10/84). Urine drug test positive for opiates within the first month (AOR: 2.01, 95% CI: 1.02-3.93) was associated with increased odds of very early disengagement. Transferring from another buprenorphine prescriber (AOR: 0.09, 95% CI: 0.01-0.70) was associated with decreased odds of very early disengagement. No characteristics were significantly associated with re-engagement.

CONCLUSIONS

Early disengagement is uncommon; however, continued opioid use appeared to be associated with higher odds of treatment disengagement and these patients may warrant additional support. Re-engagement was uncommon, suggesting the need for a more formal explicit system to encourage and facilitate re-engagement among patients who disengage.

Buprenorphine dosing choices in specific populations: review of expert opinion

INTRODUCTION

Treatment of opioid dependence with buprenorphine improves outcomes. Typical dosing ranges for all patients from clinical evidence and as defined in the product information are wide. For specific groups with complex clinical scenarios, there is no clear consensus on dosing choices to achieve best possible outcomes.

AREAS COVERED

The doses of buprenorphine used in 6 European countries was reviewed. A review of published evidence supported rapid induction with buprenorphine and the benefits of higher doses but did not identify clearly useful guidance on dosing choices for groups with complex clinical scenarios. An expert group of physicians with experience in addiction care participated in a discussion meeting to share clinical practice experience and develop a consensus on dosing choices.

EXPERT OPINION

There was general agreement that treatment outcomes can be improved by optimising buprenorphine doses in specific subgroups. Specific groups in whom buprenorphine doses may be too low and who could have better outcomes with optimised dosing were identified on the basis of clinical practice experience. These groups include people with severe addiction, high tolerance to opioids, and psychiatric comorbidities. In these groups it is recommended to review dosing choices to ensure buprenorphine dosing is sufficient.

Retention in medication-assisted treatment for opiate dependence: A systematic review

Retention in medication-assisted treatment among opiate-dependent patients is associated with better outcomes. This systematic review (55 articles, 2010-2014) found wide variability in retention rates (i.e., 19%-94% at 3-month, 46%-92% at 4-month, 3%-88% at 6-month, and 37%-91% at 12-month follow-ups in randomized controlled trials), and identified medication and behavioral therapy factors associated with retention. As expected, patients who received naltrexone or buprenorphine had better retention rates than patients who received a placebo or no medication. Consistent with prior research, methadone was associated with better retention than buprenorphine/naloxone. And, heroin-assisted treatment was associated with better retention than methadone among treatment-refractory patients. Only a single study examined retention in medication-assisted treatment for longer than 1 year, and studies of behavioral therapies may have lacked statistical power; thus, studies with longer-term follow-ups and larger samples are needed. Contingency management showed promise to increase retention, but other behavioral therapies to increase retention, such as supervision of medication consumption, or additional counseling, education, or support, failed to find differences between intervention and control conditions. Promising behavioral therapies to increase retention have yet to be identified.

Substance abuse/dependence treatment: a European perspective

During the past decade, substantial progress has been made in the field of addiction medicine in Europe, particularly regarding the development of new treatment interventions, resulting in a wide range of therapeutic options for patients with substance use disorders. However, not all interventions are evidence based. Patients with cannabis and cocaine/amphetamine use disorders and special patient populations especially lack evidence-based treatment recommendations. Many patients undergo treatment that has not been scientifically evaluated for quality and efficacy. Moreover, there are large disparities regarding availability and treatment access across Europe, with the new member states of the European Union (EU) reporting long waiting lists and low treatment coverage. Even in Austria, which ranks among the countries with relatively high treatment coverage and good diversification of treatment in opioid maintenance therapy due to the availability of methadone, buprenorphine, and slow-release oral morphine (SROM), a considerable population of untreated or inadequately treated patients exists. Treatment for substance use disorders in Europe still has scope for improvement in terms of treatment availability and access, which is ideally provided by further development and implementation of evidence-based interventions.

New developments in the management of opioid dependence: focus on sublingual buprenorphine-naloxone

Opioid maintenance therapy is a well-established first-line treatment approach in opioid dependence. Buprenorphine, a partial opioid agonist, has been found by numerous studies to be an effective and safe medication in the treatment of opioid dependence. At present, buprenorphine is available as a monodrug or in a fixed 4:1 ratio combination with naloxone. A diminished risk of diversion and abuse for the buprenorphine-naloxone combination is likely but not firmly established. Conventional formulations are given sublingually to avoid the hepatic first-pass effect. A novel film tablet is available only in the US and Australia. Other novel, sustained-release formulations (implant, depot) are currently being developed and tested. Recent studies, including a Cochrane meta-analysis, suggest that the retention with buprenorphine is lower than for methadone, but that buprenorphine may be associated with less drug use. Higher doses of buprenorphine are associated with better retention rates. Buprenorphine has a ceiling effect at the opioid receptor with regard to respiratory depression, and may cause fewer fatal intoxications than methadone. Possible antidepressant effects of buprenorphine and its use in comorbid psychiatric patients has not been studied in much detail. Clinical implications are discussed.

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.

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).

Agonist-selective effects of opioid receptor ligands on cytosolic calcium concentration in rat striatal neurons

BACKGROUND

Buprenorphine is an opioid receptor ligand whose mechanism of action is incompletely understood.

METHODS

Using Ca(2+) imaging, we assessed the effects of buprenorphine, β-endorphin, and morphine on cytosolic Ca(2+) concentration [Ca(2+)](i), in rat striatal neurons.

RESULTS

Buprenorphine (0.01-1 μM) increased [Ca(2+)](i) in a dose-dependent manner in a subpopulation of rat striatal neurons. The effect of buprenorphine was largely reduced by naloxone, a non-selective opioid receptor antagonist, but not by μ, κ, δ or NOP-selective antagonists. β-Endorphin (0.1 μM) increased [Ca(2+)](i) with a lower amplitude and slower time course than buprenorphine. Similar to buprenorphine, the effect of β-endorphin was markedly decreased by naloxone, but not by opioid-selective antagonists. Morphine (0.1-10 μM), did not affect [Ca(2+)](i) in striatal neurons.

CONCLUSIONS

Our results suggest that buprenorphine and β-endorphin act on a distinct type/subtype of plasmalemmal opioid receptors or activate intracellular opioid-like receptor(s) in rat striatal neurons.