The effectiveness of different singly administered high doses of buprenorphine in reducing suicidal ideation in acutely depressed people with co-morbid opiate dependence: a randomized, double-blind, clinical trial

A synopsis of multitarget therapeutic effects of anesthetics on depression

Depression is a profound mental disorder that dampens the mood and undermines volition, which exhibited an increased incidence over the years. Although drug-based interventions remain the primary approach for depression treatment, the available medications still can't satisfy the patients. In recent years, the newly discovered therapeutic targets such as N-methyl-D-aspartate (NMDA) receptor, α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptor, and tyrosine kinase B (TrkB) have brought new breakthroughs in the development of antidepressant drugs. Moreover, it has come to light that certain anesthetics possess pharmacological mechanisms intricately linked to the aforementioned therapeutic targets for depression. At present, numerous preclinical and clinical studies have explored the therapeutic effects of anesthetic drugs such as ketamine, isoflurane, N2O, and propofol, on depression. These investigations suggested that these drugs can swiftly ameliorate patients' depression symptoms and engender long-term effects. In this paper, we provide a comprehensive review of the research progress and potential molecular mechanisms of various anesthetic drugs for depression treatment. By shedding light on this subject, we aim to facilitate the development and clinical implementation of new antidepressant drugs based on anesthetic medications.

Design of CLARO+ (Collaboration Leading to Addiction Treatment and Recovery from Other Stresses, Plus): A randomized trial of collaborative care to decrease overdose and suicide risk among patients with co-occurring disorders

BACKGROUND

The United States is mired in two intertwined epidemics of death from suicide and overdose. Opioid use disorder (OUD) and mental illness contribute to both, and individuals with co-occurring disorders (CODs) are a complex population at high risk. Although universal prevention makes sense from a public health perspective, medical and behavioral health providers often lack the time to proactively address these issues with all patients. In this study, we build upon a parent study called Collaboration Leading to Addiction Treatment and Recovery from Other Stresses (CLARO), a model of collaborative care in which care coordinators deliver preventative measures to high-risk patients and coordinate care with the patients' care team, with the goal of increasing MOUD retention and decreasing risk of suicide and overdose.

METHODS

CLARO+ adds intervention components on overdose prevention, recognition, and response training; lethal means safety counseling; and an effort to mail compassionate messages called Caring Contacts. Both CLARO and CLARO+ have been implemented at 17 clinics in New Mexico and California, and this study seeks to determine the difference in effectiveness between the two versions of the intervention. This paper describes the design protocol for CLARO+.

CONCLUSION

CLARO+ is an innovative approach that aims to supplement existing collaborative care with additional suicide and overdose prevention strategies.

CLINICALTRIALS

gov: NCT04559893.

The efficacy and safety of buprenorphine for the treatment of depression: A systematic review and meta-analysis

BACKGROUND

Depressive disorders are common. Many patients with major depression do not achieve remission with available treatments. Buprenorphine has been raised as a potential treatment for depression as well as suicidal behavior but may pose certain risks.

METHODS

A meta-analysis comparing the efficacy, tolerability, and safety of buprenorphine (or combinations such as buprenorphine/samidorphan) versus control in improving symptoms in patients with depression. Medline, Cochrane Database, PsycINFO, Excerpta Medica Database and The Cumulative Index to Nursing and Allied Health Literature were searched from inception through January 2, 2022. Depressive symptoms were pooled using Hedge's g with 95% Confidence Intervals (CI). Tolerability, safety, suicide outcomes were summarized qualitatively.

RESULTS

11 studies (N = 1699) met inclusion criteria. Buprenorphine had a small effect on depressive symptoms (Hedges' g 0.17, 95%CI: 0.05-0.29). Results were driven by six trials of buprenorphine/samidorphan (N = 1,343, Hedges's g 0.17, 95%CI: 0.04-0.29). One study reported significant improvement in suicidal thoughts (Least Squares Mean Change: -7.1, 95%CI: -12.0 - 2.3). Most studies found buprenorphine was well-tolerated with no evidence of abuse behavior or dependency.

CONCLUSIONS

Buprenorphine may have a small benefit for depressive symptoms. Future research should clarify the dose response relationship between buprenorphine and depression.

Endogenous opioid systems alterations in pain and opioid use disorder

Decades of research advances have established a central role for endogenous opioid systems in regulating reward processing, mood, motivation, learning and memory, gastrointestinal function, and pain relief. Endogenous opioid systems are present ubiquitously throughout the central and peripheral nervous system. They are composed of four families, namely the μ (MOPR), κ (KOPR), δ (DOPR), and nociceptin/orphanin FQ (NOPR) opioid receptors systems. These receptors signal through the action of their endogenous opioid peptides β-endorphins, dynorphins, enkephalins, and nociceptins, respectfully, to maintain homeostasis under normal physiological states. Due to their prominent role in pain regulation, exogenous opioids-primarily targeting the MOPR, have been historically used in medicine as analgesics, but their ability to produce euphoric effects also present high risks for abuse. The ability of pain and opioid use to perturb endogenous opioid system function, particularly within the central nervous system, may increase the likelihood of developing opioid use disorder (OUD). Today, the opioid crisis represents a major social, economic, and public health concern. In this review, we summarize the current state of the literature on the function, expression, pharmacology, and regulation of endogenous opioid systems in pain. Additionally, we discuss the adaptations in the endogenous opioid systems upon use of exogenous opioids which contribute to the development of OUD. Finally, we describe the intricate relationship between pain, endogenous opioid systems, and the proclivity for opioid misuse, as well as potential advances in generating safer and more efficient pain therapies.

Pharmacological Strategies for Suicide Prevention Based on the Social Pain Model: A Scoping Review

Suicidal behaviour is a public health problem whose magnitude is both substantial and increasing. Since many individuals seek medical treatment following a suicide attempt, strategies aimed at reducing further attempts in this population are a valid and feasible secondary prevention approach. An evaluation of the available evidence suggests that existing treatment approaches have a limited efficacy in this setting, highlighting the need for innovative approaches to suicide prevention. Existing research on the neurobiology of social pain has highlighted the importance of this phenomenon as a risk factor for suicide, and has also yielded several attractive targets for pharmacological strategies that could reduce suicidality in patients with suicidal ideation or a recent attempt. In this paper, the evidence related to these targets is synthesized and critically evaluated. The way in which social pain is related to the “anti-suicidal” properties of recently approved treatments, such as ketamine and psilocybin, is examined. Such strategies may be effective for the short-term reduction in suicidal ideation and behaviour, particularly in cases where social pain is identified as a contributory factor. These pharmacological approaches may be effective regardless of the presence or absence of a specific psychiatric diagnosis, but they require careful evaluation.

Association between clinically recognized suicidality and subsequent initiation or continuation of medications for opioid use disorder

BACKGROUND

Among individuals with opioid use disorder (OUD), medications for OUD (MOUD) may lower suicide risk. Therefore, it is important that individuals with OUD and suicidality receive MOUD. This study examined associations between clinically recognized suicidality and subsequent initiation or continuation of MOUD among patients with OUD in the national Veterans Health Administration (VA).

METHODS

Electronic health record data were extracted for outpatients with OUD who received VA care 10/1/2016-7/31/2017. Suicidality was measured using diagnostic codes for suicidal ideation/attempt and patient record flags. Analyses were conducted separately among patients without prior-year MOUD receipt to examine MOUD initiation, and with prior-year MOUD receipt to examine MOUD continuation. Poisson regression models estimated likelihood of MOUD receipt in the following year for patients with prior-year suicidality relative to those without. Models were adjusted for sociodemographic and clinical characteristics.

RESULTS

Among 20,085 patients with no prior-year MOUD, 12% had suicidality and 12% received MOUD in the following year. Suicidality was positively associated with MOUD initiation (adjusted incidence rate ratio [aIRR]: 1.15, 95% confidence interval [CI]: 1.04-1.28). Among 10,162 patients with prior-year MOUD, 9% had suicidality and 84% received MOUD in the following year. Suicidality was negatively associated with MOUD continuation (aIRR: 0.95, 95% CI 0.91-0.98).

CONCLUSIONS

Among VA patients with OUD, clinically recognized suicidality may increase likelihood of MOUD initiation but decrease likelihood of continuation. Efforts to increase initiation overall and to support retention for patients with suicidality are needed.

Collaboration Leading to Addiction Treatment and Recovery from Other Stresses (CLARO): process of adapting collaborative care for co-occurring opioid use and mental disorders

Background

Opioid use disorders (OUD), co-occurring with either depression and/or PTSD, are prevalent, burdensome, and often receive little or low-quality care. Collaborative care is a service delivery intervention that uses a team-based model to improve treatment access, quality, and outcomes in primary care patients, but has not been evaluated for co-occurring OUD and mental health disorders. To address this treatment and quality gap, we adapted collaborative care for co-occurring OUD and mental health disorders.

Methods

Our adapted model is called Collaboration Leading to Addiction Treatment and Recovery from Other Stresses (CLARO). We used the five-step Map of Adaptation Process (McKleroy in AIDS Educ Prev 18:59–73, 2006) to develop the model. For each step, our stakeholder team of research and clinical experts, primary care partners, and patients provided input into adaptation processes (e.g., adaptation team meetings, clinic partner feedback, patient interviews and beta-testing). To document each adaptation and our decision-making process, we used the Framework for Reporting Adaptations and Modifications-Enhanced (Wiltsey Stirman in Implement Sci 14:1–10, 2019).

Results

We documented 12 planned fidelity-consistent adaptations to collaborative care, including a mix of content, context, and training/evaluation modifications intended to improve fit with the patient population (co-occurring disorders) or the New Mexico setting (low-resource clinics in health professional shortage areas). Examples of documented adaptations include use of community health workers as care coordinators; an expanded consultant team to support task-shifting to community health workers; modified training protocols for Problem-Solving Therapy and Written Exposure Therapy to incorporate examples of treating patients for depression or PTSD with co-occurring OUD; and having care coordinators screen for patients’ social needs.

Conclusions

We completed the first three steps of the Map of Adaptation Process, resulting in a variety of adaptations that we believe will make collaborative care more acceptable and feasible in treating co-occurring OUD and mental health disorders. Future steps include evaluating the effectiveness of CLARO and documenting reactive and/or planned adaptations to the model that occur during its implementation and delivery.

Trial registration NCT04559893, NCT04634279. Registered 08 September 2020, https://clinicaltrials.gov/ct2/show/NCT04559893

Buprenorphine as a Treatment for Major Depression and Opioid Use Disorder

Rates of major depressive disorder (MDD) are disproportionally high in subjects with opioid use disorder (OUD) relative to the general population. MDD is often more severe in OUD patients, leading to compliance issues with maintenance therapies and poor outcomes. A growing body of literature suggests that endogenous opioid system dysregulation may play a role in the emergence of MDD. Buprenorphine, a mixed opioid receptor agonist/antagonist approved for the treatment of OUD and chronic pain, may have potential as a novel therapeutic for MDD, especially for patients with a dual diagnosis of MDD and OUD. This paper presents a comprehensive review of papers relevant to the assessment of buprenorphine as a treatment for MDD, OUD, and/or suicide compiled using electronic databases per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The principal goal of this literature review was to compile the clinical studies that have interrogated the antidepressant activity of buprenorphine in opioid naïve MDD patients and OUD patients with comorbid MDD. Evidence supporting buprenorphine's superiority over methadone for treating comorbid OUD and MDD was also considered. Finally, recent evidence for the ability of buprenorphine to alleviate suicidal ideation in both opioid-naïve patients and opioid-experienced patients was evaluated. Synthesizing all of this information, buprenorphine emerges as a potentially effective therapeutic for the dual purposes of treating MDD and OUD.

Opioids in cancer: The κ‑opioid receptor (Review)

The κ‑opioid receptor (KOR) is one of the primary receptors of opioids and serves a vital role in the regulation of pain, anesthesia, addiction and other pathological and physiological processes. KOR is associated with several types of cancer and may influence cancer progression. It has been proposed that KOR may represent a new tumor molecular marker and provide a novel basis for molecular targeted therapies for cancer. However, the association between KOR and cancer remains to be explored comprehensively. The present review introduces KOR and its association with different types of cancer. Improved understanding of KOR may facilitate development of novel antitumor therapies.

Treating Chronic Pain with Buprenorphine-The Practical Guide

OPINION STATEMENT

Buprenorphine has unique and favorable pharmacological properties that make it useful in a variety of clinical scenarios. It has been recommended to consider buprenorphine first-line opioid for chronic pain, especially in the elderly as it may be associated with less cognitive impairment, falls, sexual dysfunction, and sarcopenia when compared with schedule II opioids. It may be useful in patients with comorbid substance use disorder or non-medical opioid use, as there is less risk of misuse, euphoria and it may improve mood. When used to treat opioid use disorder, the training and waiver was recently waived for licensed practitioners with a DEA and any provider may prescribe buprenorphine. For many reasons outlined in this article, the popularity of using buprenorphine for analgesia continues to grow and a practitioner should consider this as an excellent and safe option for chronic pain.

Immediate and short-term efficacy of suicide-targeted interventions in suicidal individuals: A systematic review

OBJECTIVES

To address the extreme suicide risk period following a suicidal crisis, we aimed to assess the current evidence for specific healthcare system-based interventions on suicide-related outcomes within one-week or one-month in individuals with current suicidal ideation (SI) or a recent suicide attempt (SA).

METHODS

We performed a database (Medline, Academic Search Complete, PsycARTICLES, the Cochrane library, PubMed) and manual reference search for randomised controlled trials, published between March 2000 and March 2020. Antisuicidal efficacy was defined as SI, SA, or a closely related concept. Quality was assessed with the Cochrane Risk of Bias 2 tool for randomised trials.

RESULTS

Out of 34 trials, five reported ketamine or esketamine superiority over placebo in reducing SI in depressed subjects within one week, while five studies had negative findings. Single trials reported positive results for one-month antisuicidal efficacy of buprenorphine, paroxetine, a crisis response plan, and assertive case management. Most trials were underpowered and had moderate-to-high risk of bias.

CONCLUSIONS

Preliminary mixed evidence suggests the possible utility of several pharmacological (ketamine, esketamine paroxetine, and buprenorphine) and non-pharmacological (a crisis response plan, and assertive case management) interventions. Only the immediate efficacy of ketamine was supported by multiple studies, and replication is needed.

Mechanisms Underlying the Anti-Suicidal Treatment Potential of Buprenorphine

Death by suicide is a global epidemic with over 800 K suicidal deaths worlwide in 2012. Suicide is the 10th leading cause of death among Americans and more than 44 K people died by suicide in 2019 in the United States. Patients with chronic pain, including, but not limited to, those with substance use disorders, are particularly vulnerable. Chronic pain patients have twice the risk of death by suicide compared to those without pain, and 50% of chronic pain patients report that they have considered suicide at some point due to their pain. The kappa opioid system is implicated in negative mood states including dysphoria, depression, and anxiety, and recent evidence shows that chronic pain increases the function of this system in limbic brain regions important for affect and motivation. Additionally, dynorphin, the endogenous ligand that activates the kappa opioid receptor is increased in the caudate putamen of human suicide victims. A potential treatment for reducing suicidal ideation and suicidal attempts is buprenorphine. Buprenorphine, a partial mu opioid agonist with kappa opioid antagonist properties, reduced suicidal ideation in chronic pain patients with and without an opioid use disorder. This review will highlight the clinical and preclinical evidence to support the use of buprenorphine in mitigating pain-induced negative affective states and suicidal thoughts, where these effects are at least partially mediated via its kappa antagonist properties.

Characteristics of Suicides and Toxicology in a Cohort of Individuals With Opioid Use Disorder

Suicide in patients with opioid use disorder (OUD) is a complex issue. In addition to accidental intoxications, a higher prevalence of fatal suicides in patients with OUD can be found compared to the general population. In this study, suicides with a diagnosis of OUD documented in the project "Suicides, A National Survey" were extracted from our data bank. Individuals with a diagnosis of OUD in their medical history were compared to other suicides. The analyses included clinical and demographic factors as well as an investigation of suicide methods and toxicology of psychotropic drugs. For the statistical analyses, we applied chi-square tests and calculated odds ratios. Out of 6,495 suicide cases in Switzerland between 2000 and 2010, 215 individuals with a medical history of OUD could be identified. Persons in OUD cases were significantly younger than in other suicide cases (p < .001) and had more frequently a positive history for suicide attempts (p = .02). In addition, persons in OUD cases were more often female (p = .076). Intentional self-poisoning with medication was applied more often in individuals with OUD compared to other suicide methods (p < .001). When self-poisoning with drugs was compared to violent suicide methods, a combination of benzodiazepines with antidepressants was predominantly found. Our study yielded significant characteristics and risk factors for suicides in individuals with OUD. The predominant method of suicide in individuals with OUD was intended self-poisoning by medication. This knowledge is of clinical importance for the monitoring of at-risk individuals with OUD as well as for suicide prevention in this patient group.

Transdermal Buprenorphine for Acute Pain in the Clinical Setting: A Narrative Review

Transdermal buprenorphine is indicated for chronic pain management, but as its role in the clinical management of acute pain is less clear, this narrative review examines studies of the patch for acute pain, mainly in the postoperative setting. Although perhaps better known for its role in opioid rehabilitation programs, buprenorphine is also an effective analgesic that is a Schedule III controlled substance. Although buprenorphine is a partial agonist at the μ-opioid receptor, it is erroneous to think of the agent as a partial analgesic; it has full analgesic efficacy and unique attributes among opioids, such as a ceiling for respiratory depression and low “drug likeability” among those who take opioids for recreational purposes. Transdermal buprenorphine has been most thoroughly studied for acute pain control in postoperative patients. Postoperative pain follows a distinct and predictable trajectory depending on the type of surgery and patient characteristics. Overall, when the patch is applied prior to surgery and left in place for the prescribed seven days, it was associated with reduced postoperative pain, lower consumption of other analgesics, and patient satisfaction. Transdermal buprenorphine has been evaluated in clinical studies of patients undergoing gynecological surgery, hip fracture surgery, knee or hip arthroscopy/arthroplasty, shoulder surgery, and spinal surgery. Transdermal buprenorphine may also be appropriate pain medication for controlling pain during postsurgical orthopedic rehabilitation programs. Transdermal buprenorphine may result in typical opioid-associated side effects but with less frequency than other opioids. Despite clinical reservations about transdermal buprenorphine and its potential role in acute pain management in the clinical setting, clinical acceptance may be hampered by the fact that it is off-label and buprenorphine is better known as an opioid maintenance agent rather than an analgesic.

Suicide Risk and Addiction: The Impact of Alcohol and Opioid Use Disorders

Purpose of Review

Suicide is a major public health concern and a leading cause of death in the US. Alcohol and opioid use disorders (AUD/OUD) significantly increase risk for suicidal ideation, attempts, and death, and are the two most frequently implicated substances in suicide risk. We provide a brief overview of shared risk factors and pathways in the pathogenesis of AUD/OUD and suicidal thoughts and behaviors. We also review clinical recommendations on inpatient care, pharmacotherapy, and psychotherapeutic interventions for people with AUD/OUD and co-occurring suicidal ideation and behavior.

Recent Findings

Among people with an underlying vulnerability to risk-taking and impulsive behaviors, chronic alcohol intoxication can increase maladaptive coping behaviors and hinder self-regulation, thereby increasing the risk of suicide. Additionally, chronic opioid use can result in neurobiological changes that lead to increases in negative affective states, jointly contributing to suicide risk and continued opioid use. Despite significantly elevated suicide risk in individuals with AUD/OUD, there is a dearth of research on pharmacological and psychosocial interventions for co-occurring AUD/OUD and suicidal ideation and behavior.

Summary

Further research is needed to understand the effects of alcohol and opioid use on suicide risk, as well as address notable gaps in the literature on psychosocial and pharmacological interventions to lower risk for suicide among individuals with AUD/OUD.

Case Series of Patients with Opioid Use Disorder and Suicidal Ideation Treated with Buprenorphine

Introduction

Buprenorphine benefits patients with opioid use disorder (OUD) in the emergency department (ED), but its efficacy for OUD patients with suicidal ideation (SI) in the ED is unknown.

Case Series

We present a case series of 14 OUD patients with SI who were given buprenorphine and a referral to outpatient substance use treatment in the ED. All experienced SI resolution, engaged with outpatient services, and remained in outpatient substance use treatment 30 days after ED discharge.

Conclusion

Our data provide evidence for the feasibility of starting buprenorphine in OUD patients with SI in the ED, and suggest that buprenorphine may be useful in helping to resolve SI for these patients. Future research with larger samples is needed.

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.

Case Report: Buprenorphine-A Treatment for Psychological Pain and Suicidal Ideation?

BACKGROUND AND OBJECTIVES

Buprenorphine is commonly used to manage opioid use disorder; however, the literature describes its potential role in treating treatment-resistant depression.

METHODS

We present a patient with bipolar disorder and opioid use disorder, who presented status post-suicide attempt.

RESULTS

After initiating buprenorphine-naloxone, the patient reported rapid improvement in depressive symptoms, pain, and suicidal ideation.

DISCUSSION AND CONCLUSIONS

This case demonstrates buprenorphine's antisuicidal and mood-stabilizing capabilities, potentially via antagonizing κ-opioid receptors as well as reinstating the balance between reward and antireward circuitry.

SCIENTIFIC SIGNIFICANCE

This case highlights buprenorphine-naloxone as a treatment for both treatment-resistant depression and opioid use disorder, as well as buprenorphine's rapid antidepressant, analgesic, and antisuicidal effects. (Am J Addict 2021;30:80-82).

Buprenorphine buccal film for chronic pain management

Buprenorphine is a Schedule III opioid with unique pharmacodynamic and pharmacokinetic properties that contribute to effective analgesia and fewer safety risks than other opioids. This review article focuses on the buccal film formulation, which is preferable to other buprenorphine formulations on the basis of bioavailability, safety and efficacy. The clinical studies reviewed here confirm that buprenorphine buccal film offers effective and continuous pain relief that is generally well tolerated, with no cases of respiratory depression reported in any of the studies. On the basis of these clinical data and individual patient risk/benefit assessments, clinicians should consider utilizing buprenorphine buccal film as a first-line opioid treatment for chronic pain over other buprenorphine formulations or other opioids.

A Narrative Pharmacological Review of Buprenorphine: A Unique Opioid for the Treatment of Chronic Pain

Buprenorphine is a Schedule III opioid analgesic with unique pharmacodynamic and pharmacokinetic properties that may be preferable to those of Schedule II full μ-opioid receptor agonists. The structure of buprenorphine allows for multimechanistic interactions with opioid receptors μ, δ, κ, and opioid receptor-like 1. Buprenorphine is considered a partial agonist with very high binding affinity for the μ-opioid receptor, an antagonist with high binding affinity for the δ- and κ-opioid receptors, and an agonist with low binding affinity for the opioid receptor-like 1 receptor. Partial agonism at the μ-opioid receptor does not provide partial analgesia, but rather analgesia equivalent to that of full μ-opioid receptor agonists. In addition, unlike full μ-opioid receptor agonists, buprenorphine may have a unique role in mediating analgesic signaling at spinal opioid receptors while having less of an effect on brain receptors, potentially limiting classic opioid-related adverse events such as euphoria, addiction, or respiratory depression. The pharmacokinetic properties of buprenorphine are also advantageous in a clinical setting, where metabolic and excretory pathways allow for use in patients requiring concomitant medications, the elderly, and those with renal or hepatic impairment. The unique pharmacodynamic and pharmacokinetic properties of buprenorphine translate to an effective analgesic with a potentially favorable safety profile compared with that of full μ-opioid receptor agonists for the treatment of chronic pain.

Classics in Chemical Neuroscience: Buprenorphine

Buprenorphine has not only had an interdisciplinary impact on our understanding of key neuroscience topics like opioid pharmacology, pain signaling, and reward processing but has also been a key influence in changing the way that substance use disorders are approached in modern medical systems. From its leading role in expanding outpatient treatment of opioid use disorders to its continued influence on research into next-generation analgesics, buprenorphine has been a continuous player in the ever-evolving societal perception of opioids and substance use disorder. To provide a multifaceted account on the enormous diversity of areas where this molecule has made an impact, this article discusses buprenorphine's chemical properties, synthesis and development, pharmacology, adverse effects, manufacturing information, and historical place in the field of chemical neuroscience.

Understanding Buprenorphine for Use in Chronic Pain: Expert Opinion

OBJECTIVE

An expert panel convened to reach a consensus on common misconceptions surrounding buprenorphine, a Schedule III partial µ-opioid receptor agonist indicated for chronic pain. The panel also provided clinical recommendations on the appropriate use of buprenorphine and conversion strategies for switching to buprenorphine from a full µ-opioid receptor agonist for chronic pain management.

METHODS

The consensus panel met on March 25, 2019, to discuss relevant literature and provide recommendations on interpreting buprenorphine as a partial µ-opioid receptor agonist, prescribing buprenorphine before some Schedule II, III, or IV options, perioperative/trauma management of patients taking buprenorphine, and converting patients from a full µ-opioid receptor agonist to buprenorphine.

RESULTS

The panel recommended that buprenorphine's classification as a partial µ-opioid receptor agonist not be clinically translated to mean partial analgesic efficacy. The panel also recommended that buprenorphine be considered before some Schedule II, III, or IV opioids in patients with a favorable risk/benefit profile on the basis of metabolic factors, abuse potential, and tolerability and that buprenorphine be continued during the perioperative/trauma period. In addition, switching patients from a full µ-opioid receptor agonist to buprenorphine should be considered with no weaning period at starting doses that are based on the previous opioid dose.

CONCLUSIONS

These recommendations provide a framework for clinicians to address most clinical scenarios regarding buprenorphine use. The overall consensus of the panel was that buprenorphine is a unique Schedule III opioid with favorable pharmacologic properties and a safety profile that may be desirable for chronic pain management.

Buprenorphine: prospective novel therapy for depression and PTSD

BACKGROUND

Depression and post-traumatic stress disorder (PTSD) are leading causes of disability and loss of life by suicide. Currently, there are less than satisfactory medical solutions to treat these mental disorders. Here, we explore recent preclinical and clinical studies demonstrating the potential of using buprenorphine to treat major depressive disorder, treatment-resistant depression, and PTSD.

METHOD

Bibliographic databases were searched to include preclinical and clinical studies demonstrating the therapeutic potential of buprenorphine and the involvement of the kappa opioid receptor (KOR) in mediating these effects.

RESULTS

Original clinical studies examining the effectiveness of buprenorphine to treat depression were mixed. The majority of participants in the PTSD studies were males and suffer from chronic pain and/or substance use disorders. Nonetheless, these recent studies and analyses established proof of concept warranting farther investigations. Additionally, KOR likely mediates the antidepressant and some of the anxiolytic effects of buprenorphine. Still, it appears that the full spectrum of buprenorphine's beneficial effects might be due to activity at other opioid receptors as well.

CONCLUSIONS

Pharmaceuticals' abilities to treat medical conditions directly relates to their ability to act upon the endogenous biological systems related to the conditions. Thus, these recent findings are likely a reflection of the central role that the endogenous opioid system has in these mental illnesses. Further studies are necessary to study the involvement of endogenous opioid systems, and specifically KOR, in mediating buprenorphine's beneficial effects and the ability to treat these medical conditions while minimizing risks for misuse and diversion.

Kappa Opioid Receptor Antagonists as Potential Therapeutics for Stress-Related Disorders

Exposure to stressful stimuli activates kappa opioid receptor (KOR) signaling, a process known to produce aversion and dysphoria in humans and other species. This endogenous opioid system is dysregulated in stress-related disorders, specifically in major depressive disorder (MDD). These findings serve as the foundation for a growing interest in the therapeutic potential of KOR antagonists as novel antidepressants. In this review, data supporting the hypothesis of dysregulated KOR function in MDD are considered. The clinical data demonstrating the therapeutic efficacy and safety of selective and mixed opioid antagonists are then presented. Finally, the preclinical evidence illustrating the induction of behaviors relevant to the endophenotypes of MDD and KOR antagonist activity in stress-naïve and stress-exposed animals is evaluated. Overall, this review highlights the emergent literature supporting the pursuit of KOR antagonists as novel therapeutics for MDD and other stress-related disorders.

The Role of Opiates in Social Pain and Suicidal Behavior

With more than 800,000 deaths by suicide each year and 20 to 30 times more suicide attempts worldwide, suicide is a major public health problem. Current treatments of SB are mainly based on pharmacological treatments that are not specific of SB (e.g. antidepressants), and new therapeutic targets are urgently needed. Recent data strengthen the ancient conception pain (social, psychic, physical) that is at the core of the suicidal process and should be incorporated in the clinical assessment of suicide risk. Then, the mechanisms involved in the regulation of pain may open new avenues regarding therapeutic perspectives. Opiates appear to be a promising candidate in treatment of SB. Indeed, since the last two decades, growing evidences suggest an implication of the opioid system in the pathophysiology of SB, this conduct to the elaboration of randomized controlled trials (RCTs) using opiates in patients with SB. Results suggesting an anti-suicidal effect of buprenorphine and the potential opioidergic-related anti-suicidal effect of ketamine both contribute to the growing interest in opiates use in SB. In this review, we will summarize a large part of the evidence that leads researchers and clinicians to be interested in the use of opiates for SB treatment and discuss on new opioid pharmacological options for suicidal patients.

Prevention of suicide and reduction of self-harm among people with substance use disorder: A systematic review and meta-analysis of randomised controlled trials

BACKGROUND

People with substance use disorder (SUD) are at significantly greater risk of suicide compared with the general population. In recent years the number of suicides resulting from drug poisoning in England and Wales has increased. We sought to identify and evaluate the effect of interventions to prevent suicide or reduce self-harm among people with SUD.

METHODS

We conducted a systematic review of randomised controlled trials (RCTs) of interventions for people with SUD that included suicide or self-harm-related primary outcomes. We searched Cochrane Central Register of Controlled Trials (CENTRAL), PsycINFO, PubMed, Embase and Web of Science from inception until 13th January 2019. Studies were assessed for bias using the Cochrane Risk of Bias 2 tool. A random effects meta-analysis of standardised mean differences (SMD) was conducted.

RESULTS

We identified six RCTs from four countries (Australia, Iran, the United States of America and the United Kingdom) comprising 468 participants in total. All but one study investigated psychosocial interventions. On average across studies there was weak evidence of a small positive effect of interventions on suicide or self-harm outcomes (d=-0.20, 95% CI=-0.39-0.00).

LIMITATIONS

Studies were heterogeneous in terms of population, intervention, controls and outcome. There were some concerns regarding bias for all trials. All trials were liable to type II error.

CONCLUSIONS

Evidence is currently lacking regarding the effectiveness of interventions to prevent suicide and reduce self-harm amongst people with SUD.

Examination of pain threshold and neuropeptides in patients with acute suicide risk

INTRODUCTION

One of the main challenges in suicide prevention is the limited understanding of the biological mechanisms underlying suicide. Recent findings suggest impairments in pain processing in acutely suicidal patients. However, little is known about the biological factors that may drive these discrete physiological abnormalities. In this study, we examined plasma peptides involved in analgesic and inflammatory responses and physical pain threshold in acutely suicidal patients.

METHODS

Thirty-seven depressed patients of both sexes hospitalized for severe suicidal ideation or a recent suicide attempt were characterized clinically including history of suicidal ideation and behavior. Psychological and physical pain, and pressure pain threshold was also measured. Plasma levels of β-endorphin, neurotensin, agouti-related protein (AgRP), C-reactive protein (CRP), adrenocorticotropic hormone (ACTH), and brain-derived neurotrophic factor (BDNF) were run in Milliplex multiplex assays.

RESULTS

The number of lifetime suicide attempts was positively correlated with β-endorphin (r = 0.702; p = 0.007), and neurotensin (r = 0.728, p = 0.007) plasma levels. Higher pain threshold was measured in the suicide attempt group as compared to the suicidal ideation group. Pain threshold was strongly and negatively associated with CRP plasma levels (r = -0.548; p < 0.001). In patients reporting chronic pain, lower AgRP levels and lower pain threshold were observed (t = 4.472; p = 0.001).

CONCLUSION

Our results suggest that abnormalities in the opioid and neurotensin systems may underlie the increase in pain threshold found in suicide attempters, and possibly risk for suicidal behavior. Targeting pain circuits and systems may provide therapeutic mechanisms for suicide prevention.

Safety And Efficacy Of The Unique Opioid Buprenorphine For The Treatment Of Chronic Pain

BACKGROUND

Chronic pain is associated with decreased quality of life and is one of the most common reasons adults seek medical care, making treatment imperative for many aspects of patient well-being. Chronic pain management typically involves the use of Schedule II full μ-opioid receptor agonists for pain relief; however, the increasing prevalence of opioid addiction is a national crisis that is impacting public health and social and economic welfare. Buprenorphine is a Schedule III partial μ-opioid receptor agonist that is an equally effective but potentially safer treatment option for chronic pain than full μ-opioid receptor agonists. The purpose of this review is to provide an overview of the clinical efficacy and safety of the transdermal and buccal formulations of buprenorphine, which are approved by the Food and Drug Administration for chronic pain, compared with that of extended-release full μ-opioid receptor agonists.

METHODS

Controlled or randomized controlled clinical trial information was retrieved from EMBASE, Medline, and PubMed using the search terms "buprenorphine" AND "chronic" AND "pain."

RESULTS

A total of 33 clinical studies were ultimately used in this review, including 29 (88%) on transdermal buprenorphine and 4 (12%) on buprenorphine buccal film. Although the measure of pain intensity varied among studies, each of these 33 trials demonstrated efficacy for buprenorphine in pain relief. A total of 28 studies also assessed safety, with each concluding that buprenorphine was generally well tolerated.

CONCLUSION

Comparison of current clinical data along with results of responder and safety analyses support the use of buprenorphine over full μ-opioid receptor agonists for effective preferential treatment of chronic pain; however, head-to-head clinical studies are warranted.

Suicide and suicide risk

Although recent years have seen large decreases in the overall global rate of suicide fatalities, this trend is not reflected everywhere. Suicide and suicidal behaviour continue to present key challenges for public policy and health services, with increasing suicide deaths in some countries such as the USA. The development of suicide risk is complex, involving contributions from biological (including genetics), psychological (such as certain personality traits), clinical (such as comorbid psychiatric illness), social and environmental factors. The involvement of multiple risk factors in conveying risk of suicide means that determining an individual's risk of suicide is challenging. Improving risk assessment, for example, by using computer testing and genetic screening, is an area of ongoing research. Prevention is key to reduce the number of suicide deaths and prevention efforts include universal, selective and indicated interventions, although these interventions are often delivered in combination. These interventions, combined with psychological (such as cognitive behavioural therapy, caring contacts and safety planning) and pharmacological treatments (for example, clozapine and ketamine) along with coordinated social and public health initiatives, should continue to improve the management of individuals who are suicidal and decrease suicide-associated morbidity.

Polymorphism A118G of opioid receptor mu 1 (OPRM1) is associated with emergence of suicidal ideation at antidepressant onset in a large naturalistic cohort of depressed outpatients

Antidepressants have been the object of an international controversy for about thirty years. Some patients are inclined to develop suicidal ideation (SI) at antidepressant onset; this phenomenon is known as Treatment Emergent Suicidal Ideation (TESI), and it has conducted regulatory bodies to prompt warnings on antidepressants. Since, few studies have explored the pharmacogenomics of TESI. Given the growing body of evidence connecting the opioidergic system with suicidal behavior (particularly mu opioid receptor (MOR)), we decided to examine the relationship between two genetic polymorphisms (SNPs) in the opioidergic system and TESI in a sample of 3566 adult depressed outpatients. General practitioners and psychiatrists throughout France followed participants for 6 weeks after an initial prescription of tianeptine, an antidepressant treatment with mu agonism. Suicidal ideation was assessed with the item 10 of the Montgomery-Asberg Depression Rating Scale (item dedicated to SI) at baseline, and after 2 weeks, 4 weeks and 6 weeks. We analysed rs1799971 from the OPRM1 gene and rs105660 from the OPRK1 gene. Within the sample, 112 patients reported TESI while 384 did not. We found a significant association between AA genotype of rs1799971 and TESI even after adjustment for potential cofounders (OR = 1.93, 95% CI = [1.07; 3.49]; p-value = 0.03). On the other hand there were no significant association between rs1799971 and rs105560 with worsening of suicidal ideation or lifetime suicide attempts. Nevertheless, our results suggest a possible involvement of opioidergic system in TESI.