Opioid use disorders (OUD) and overdoses are ever-evolving public health threats that continue to grow in incidence and prevalence in the United States and abroad. Current treatments consist of opioid receptor agonists and antagonists, which are safe and effective but still suffer from some limitations. Murine and humanized monoclonal antibodies (mAb) have emerged as an alternative and complementary strategy to reverse and prevent opioid-induced respiratory depression. To explore antibody applications beyond traditional heavy-light chain mAbs, we identified and biophysically characterized a novel single-domain antibody specific for fentanyl from a camelid variable-heavy-heavy (VHH) domain phage display library. Structural data suggested that VHH binding to fentanyl was facilitated by a unique domain-swapped dimerization mechanism, which accompanied a rearrangement of complementarity-determining region (CDR) loops leading to the formation of a fentanyl-binding pocket. Structure-guided mutagenesis further identified an amino acid substitution that improved the affinity and relaxed the requirement for dimerization of the VHH in fentanyl binding. Our studies demonstrate VHH engagement of an opioid and inform on how to further engineer a VHH for enhanced stability and efficacy, laying the groundwork for exploring the in vivo applications of VHH-based biologics against OUD and overdose.

UNASSIGNED: This study examined whether there is an association between opioid-related mortality and surgical procedures.
UNASSIGNED: A case-control study design using deceased controls compared individuals with and without opioid death and their exposure to common surgeries in the preceding 4 years. This population-based study used linked death and hospitalization databases in Canada (excluding Quebec) from January 01, 2008 to December 31, 2017. Cases of opioid death were identified and matched to 5 controls who died of other causes by age (±4 years), sex, province of death, and date of death (±1 year). Patients with HIV infection and alcohol-related deaths were excluded from the control group. Logistic regression was used to determine if there was an association between having surgery and death from an opioid-related cause by estimating the crude and adjusted odds ratios (ORs) with the corresponding 95% confidence interval (CI). Covariates included sociodemographic characteristics, comorbidities, and the number of days of hospitalization in the previous 4 years.
UNASSIGNED: We identified 11,865 cases and matched them with 59,345 controls. About 11.2% of cases and 12.5% of controls had surgery in the 4 years before their death, corresponding to a crude OR of 0.89 (95% CI: 0.83-0.94). After adjustment, opioid mortality was associated with surgical procedure with OR of 1.26 (95% CI: 1.17-1.36).
UNASSIGNED: After adjusting for comorbidities, patients with opioid mortality were more likely to undergo surgical intervention within 4 years before their death. Clinicians should enhance screening for opioid use and risk factors when considering postoperative opioid prescribing.

Maintenance therapy with buprenorphine and methadone is the gold standard pharmacological treatment for opioid use disorder (OUD). Despite these compounds demonstrating substantial efficacy, a significant number of patients do not show optimal therapeutic responses. The abuse liability of these medications is also a concern. Here we used rats to explore the therapeutic potential of the new long-acting pan-opioid agonist Cebranopadol in OUD. We tested the effect of cebranopadol on heroin self-administration and yohimbine-induced reinstatement of heroin seeking. In addition, we evaluated the abuse liability potential of cebranopadol in comparison to that of heroin under fixed ratio 1 (FR1) and progressive ratio (PR) operant self-administration contingencies. Oral administration of cebranopadol (0, 25, 50μg/kg) significantly attenuated drug self-administration independent of heroin dose (1, 7, 20, 60μg/inf). Cebranopadol also reduced the break point for heroin (20 μg/inf). Finally, pretreatment with cebranopadol significantly attenuated yohimbine-induced reinstatement of drug seeking. In abuse liability experiments under FR1 contingency, rats maintained responding for heroin (1, 7, 20, 60μg/inf) to a larger extent than cebranopadol (0.03, 0.1, 0.3, 1.0, 6.0μg/inf). Under PR contingency, heroin maintained responding at high levels at all except the lowest dose, while the break point (BP) for cebranopadol did not differ from that of saline. Together, these data indicate that cebranopadol is highly efficacious in attenuating opioid self-administration and stress-induced reinstatement, while having limited abuse liability properties. Overall, the data suggest clinical potential of this compound for OUD treatment.

Background: Hyperkatifeia describes amplified emotional and motivational withdrawal due to addiction-related sensitization of brain-stress-systems. Hyperkatifeia has been proposed as a target for addiction treatment development. However, translation of basic research in this area will require new tools designed to measure hyperkatifeia and related phenomena outside of laboratory settings.Objectives: We define a novel concept, withdrawal interference, and introduce a new tool - the Withdrawal Interference Scale (WIS) - which measures the impact of withdrawal on daily life among individuals with OUD or AUD.Methods: Described are the combined results of three separate cross-sectional studies. The structural validity, convergent validity, construct validity, trans-diagnostic (AUD/OUD) configural, metric, and scalar invariance, internal consistency, and composite reliability of WIS was tested among three independent samples of 1) treatment-seeking adults with OUD (n = 132), 2) treatment-seeking adults with AUD (n = 123), and 3) non-treatment-seeking adults with OUD (n = 140). Males numbered 218 and females were 163.Results: WIS exhibited structural validity (1 factor), convergent validity (average variance extracted .670-.676), construct validity, trans-diagnostic configural (χ2/df = 2.10), metric (Δχ2 = 5.70, p = .681), and scalar invariance (Δχ2 = 12.34, p = .338), internal consistency (α .882-928), and composite reliability (.924-.925).Conclusion: These results suggest WIS is a valid and reliable instrument for measuring withdrawal-related life disruption in AUD and OUD. Further, given our findings of transdiagnostic measurement invariance, WIS scores of individuals with AUD and OUD can be meaningfully compared in future statistical analyses.

BACKGROUND: Studies have found associations between Opioid Agonist Maintenance Treatment during incarceration and reduced recidivism among recently released formerly incarcerated persons. However, the role of community-based Opioid Agonist Maintenance Treatment in reducing recidivism post-release remains less explored. This study examines whether pre-release arranged, prison-to-rehabilitation Opioid Agonist Maintenance Treatment in the community following release is associated with reduced rates and lengths of re-incarceration among justice-involved individuals with Opioid Use Disorder.
METHODS: A retrospective matched cohort study was conducted using linked records of 208 individuals with a history of Opioid Use Disorder and treatment during their incarceration. The primary predictor variable was the duration of Opioid Agonist Maintenance Treatment, with re-incarceration rates and lengths of stay after re-incarceration being the primary outcomes examined.
RESULTS: Analysis showed a significant decrease in re-incarcerations and or lengths of stay in prison among those who have been re-incarcerated and have undergone Opioid Agonist Maintenance Treatment in the community for >24 months.
CONCLUSIONS: Maintaining Opioid Agonist Maintenance Treatment over 24 months may reduce re-incarcerations, and may be significantly associated with a reduction in the length of prison stay for re-incarcerated individuals. The effects were consistent across the overall population and the individuals receiving the treatment. Various other unmeasured factors, including judicial discretion, individual motivation, type of offense, and employment status, could influence this association.

Chronic pain and opioid use disorder (OUD) are major public health problems, with rising opioid-related overdose deaths linked to increased opioid prescriptions for pain management. Novel treatment approaches for these commonly comorbid disorders are needed. Growing evidence supports a role for glial activation for both chronic pain and substance use disorders, including OUD. This review provides an overview of glial modulators as a novel treatment approach for comorbid pain and OUD. We aim to synthesize clinical studies investigating the efficacy of glial modulators in treating these comorbid disorders. We conducted a literature search of PubMed and Google Scholar databases in October 2023 to identify relevant clinical trials. The included studies varied in terms of patient population, study methodology and outcomes assessed, and were often limited by small sample sizes and other methodological issues. Additionally, several glial modulators have yet to be studied for chronic pain and OUD. Despite these limitations, these studies yielded positive signals that merit further investigation. Both chronic pain and OUD remain significant public health problems, with many treatment challenges. Glial modulators continue to hold promise as novel therapeutics for comorbid pain and OUD, given positive indications that they can improve pain measures, and reduce addiction-related outcomes. As our understanding of the mechanisms underlying the contributions of glial modulators to pain and addiction behaviours deepens, we will be better equipped to identify more specific therapeutic targets for chronic pain and OUD.

The rise of psychedelics in contemporary medicine has sparked interest in their potential therapeutic applications. While traditionally associated with countercultural movements and recreational use, recent research has shed light on the potential benefits of psychedelics in various mental health conditions. In this review, we explore the possible role of psychedelics in the management of chronic pain and opioid use disorder (OUD), 2 critical areas in need of innovative treatment options. Pain control remains a significant clinical challenge, particularly for individuals with OUD and those who receive long-term opioid therapy who develop marked tolerance to opioid-induced analgesia. Despite the magnitude of this problem, there is a scarcity of controlled studies investigating pain management alternatives for these populations. Drawing from preclinical and human evidence, we highlight the potential of psychedelics to act on shared neurobiological substrates of chronic pain and OUD, potentially reversing pain- and opioid-induced neuroadaptations, such as central sensitization. We elaborate on the multifaceted dimensions of the pain experience (sensory, affective and cognitive) and their intersections that overlap with opioid-related phenomena (opioid craving and withdrawal), hypothesizing how these processes can be modulated by psychedelics. After summarizing the available clinical research, we propose mechanistic insights and methodological considerations for the design of future translational studies and clinical trials, building on a shared clinical and neurobiological understanding of chronic pain and OUD. Our intention is to provide timely perspectives that accelerate the development and exploration of novel therapeutics for chronic pain and OUD amidst the escalating opioid crisis.

Integration of medication-assisted treatment (MAT) for opioid use disorder in primary care settings is an emerging health care delivery model that supports increased access to specialized care but requires primary care provider engagement. Examining the characteristics of providers who provide this service is key to informing targeted recruitment. Using administrative and supplemental data collected during license renewal, this study aimed to identify the characteristics of primary care physicians and nurse practitioners (NPs) associated with greater odds of providing MAT in their practice. A retrospective observational study was conducted using a descriptive correlational design. The analysis included 5259 physicians and 3486 NPs who renewed their licenses electronically in 2021 and specialized in primary care or psychiatry. Chi-square and logistic regression analyses were conducted to identify the demographic and clinical characteristics of physicians and NPs associated with MAT participation in their practice. Physicians had a higher odds ratio (OR) of providing MAT if they were younger than 35 years (OR = 1.334; P = .0443), practiced in a federally qualified health center (OR = 3.101, P < .0001), and offered a sliding fee scale in their practice (OR = 2.046; P < .0001). Likewise, NPs had higher odds of providing MAT if they practiced in a public or community health center (OR = 3.866; P < .0001). The results of this study highlight the personal and professional characteristics of physicians and NPs associated with higher odds of providing MAT. These findings may have implications for the recruitment and sustainability of MAT integration in primary care.

Background: Discovery of modifiable factors influencing subjective withdrawal experience might advance opioid use disorder (OUD) research and precision treatment. This study explores one factor - withdrawal catastrophizing - a negative cognitive and emotional orientation toward withdrawal characterized by excessive fear, worry or inability to divert attention from withdrawal symptoms.Objectives: We define a novel concept - withdrawal catastrophizing - and present an initial evaluation of the Withdrawal Catastrophizing Scale (WCS).Methods: Prospective observational study (n = 122, 48.7% women). Factor structure (exploratory factor analysis) and internal consistency (Cronbach\'s α) were assessed. Predictive validity was tested via correlation between WCS and next-day subjective opiate withdrawal scale (SOWS) severity. The clinical salience of WCS was evaluated by correlation between WCS and withdrawal-motivated behaviors including risk taking, OUD maintenance, OUD treatment delay, history of leaving the hospital against medical advice and buprenorphine-precipitated withdrawal.Results: WCS was found to have a two-factor structure (distortion and despair), strong internal consistency (α = .901), and predictive validity - Greater withdrawal catastrophizing was associated with next-day SOWS (rs (99) = 0.237, p = .017). Withdrawal catastrophizing was also correlated with risk-taking behavior to relieve withdrawal (rs (119) = 0.357, p < .001); withdrawal-motivated OUD treatment avoidance (rs (119) = 0.421, p < .001), history of leaving the hospital against medical advice (rs (119) = 0.373, p < .001) and buprenorphine-precipitated withdrawal (rs (119) = 0.369, p < .001).Conclusion: This study provides first evidence of withdrawal catastrophizing as a clinically important phenomenon with implications for the future study and treatment of OUD.

Various studies showed that people with substance use disorder use cannabis to reduce withdrawal or dose of their main drug. Using a questionnaire about their cannabis use, 118 participants in an opioid maintenance treatment (OMT) in Germany were examined regarding this strategy. 60% reported to use cannabis. Of those, 72% were using cannabis in the suggested way. Cannabis was used to substitute for, e.g., heroin (44.8%) and benzodiazepines (16.4%). We also asked for an estimation of how good cannabis was able to substitute for several substances (in German school grades (1 till 6)); heroin average grade: 2.6 ± 1.49. Besides that we asked about the idea of cannabis as \"self-medication\", e.g., to reduce pain (47%) and about negative consequences from cannabis use. Our results suggest to consider the use of cannabis by patients in OMT rather as a harm reduction strategy to reduce the intake of more dangerous drugs.