Injectable extended-release naltrexone for opioid dependence: a double-blind, placebo-controlled, multicentre randomised trial

Patients with Opioid Use Disorder Choosing Treatment with Extended-Release Naltrexone: A 6-Month Naturalistic Study

INTRODUCTION

The treatment efficacy of extended-release naltrexone (XR-NTX) for opioid use disorder (OUD) has been demonstrated in several studies, but not in naturalistic settings where opioid agonist treatment (OAT) is freely accessible. This study aimed to examine the different treatment outcomes of XR-NTX in a setting where the participants freely chose XR-NTX as a treatment option instead of OAT.

METHODS

This was a 24-week open-label clinical prospective cohort study conducted in an outpatient setting at five hospitals in Norway. The study included 161 participants aged 18-65 years with OUD. Intramuscular injections of XR-NTX were administered every 4 weeks for 24 weeks. Measurements included retention in treatment, reasons for treatment discontinuation, days of use of opioids, other illicit substances and alcohol, level of heroin craving, treatment satisfaction, and adverse events (AEs).

RESULTS

Of 161 included participants, the mean age was 38 years, and 24% were women; 138 received at least one dose of the study medication (modified intention-to-treat [MITT] population), and mean time in treatment was 18.1 weeks (95% CI: 16.8-19.4). The majority of the MITT population (84; 60.9%) completed 24 weeks of treatment in the study. There was a significant decrease in the overall use of opioids (p < 0.001) and the use of alcohol, and other illicit substances were low. The participants generally reported high treatment satisfaction and low heroin cravings. Those who completed the 24 weeks of treatment reported significantly fewer days of opioid use (p < 0.001) and higher treatment satisfaction (p < 0.001) than those who discontinued treatment before 24 weeks. No serious AEs were directly related to XR-NTX use.

CONCLUSION

This study demonstrated high retention rates, decreased opioid use, and low use of other illicit substances and alcohol. Participants also reported low cravings for heroin and high treatment satisfaction. Completion of the full 24-week treatment resulted in lower opioid use and increased treatment satisfaction compared to those who discontinued treatment before 24 weeks. The observed higher retention and reduced opioid use, compared to other studies, may be attributed to participants' strong motivation for opioid abstinence facilitated by XR-NTX treatment.

Emergency department management of opioid use disorder in pediatric patients

Opioid use disorder (OUD) has emerged as a significant public health crisis affecting individuals across all age groups. However, there remains a critical gap in understanding the specific nuances and challenges associated with OUD in pediatric populations. This article provides a comprehensive review of the epidemiology, definition of OUD, screening recommendations for OUD, and evidence-based management strategies for OUD in pediatric patients.

Self-help groups and opioid use disorder treatment: An investigation using a machine learning-assisted robust causal inference framework

OBJECTIVES

This study investigates the impact of participation in self-help groups on treatment completion among individuals undergoing medication for opioid use disorder (MOUD) treatment. Given the suboptimal adherence and retention rates for MOUD, this research seeks to examine the association between treatment completion and patient-level factors. Specifically, we evaluated the causal relationship between self-help group participation and treatment completion for patients undergoing MOUD.

METHODS

We used the Substance Abuse and Mental Health Services Administration's (SAMHSA) Treatment Episode Data Set: Discharges (TEDS-D) from 2015 to 2019. The data are filtered by the patient's opioid use history, demographics, treatment modality, and other relevant information. In this observational study, machine learning models (Lasso Regression, Decision Trees, Random Forest, and XGBoost) were developed to predict treatment completion. Outcome Adaptive Elastic Net (OAENet) was used to select confounders and outcome predictors, and the robust McNemars test was used to evaluate the causal relationship between self-help group participation and MOUD treatment completion.

RESULTS

The machine-learning models showed a strong association between participation in self-help groups and treatment completion. Our causal analysis demonstrated an average treatment effect on treated (ATT) of 0.260 and a p-value < 0.0001 for the robust McNemars test.

CONCLUSIONS

Our study demonstrates the importance of participation in self-help groups for MOUD treatment recipients. We found that participation in MOUD along with self-help groups caused higher chances of treatment completion than MOUD alone. This suggests that policymakers should consider further integrating self-help groups into the treatment for OUD to improve the adherence and completion rate.

Enhancing translation: A need to leverage complex preclinical models of addictive drugs to accelerate substance use treatment options

Preclinical models of addictive drugs have been developed for decades to model aspects of the clinical experience in substance use disorders (SUDs). These include passive exposure as well as volitional intake models across addictive drugs and have been utilized to also measure withdrawal symptomatology and potential neurobehavioral mechanisms underlying relapse to drug seeking or taking. There are a number of Food and Drug Administration (FDA)-approved medications for SUDs, however, many demonstrate low clinical efficacy as well as potential sex differences, and we also note gaps in the continuum of care for certain aspects of clinical experiences in individuals who use drugs. In this review, we provide a comprehensive update on both frequently utilized and novel behavioral models of addiction with a focus on translational value to the clinical experience and highlight the need for preclinical research to follow epidemiological trends in drug use patterns to stay abreast of clinical treatment needs. We then note areas in which models could be improved to enhance the medications development pipeline through efforts to enhance translation of preclinical models. Next, we describe neuroscience efforts that can be leveraged to identify novel biological mechanisms to enhance medications development efforts for SUDs, focusing specifically on advances in brain transcriptomics approaches that can provide comprehensive screening and identification of novel targets. Together, the confluence of this review demonstrates the need for careful selection of behavioral models and methodological parameters that better approximate the clinical experience combined with cutting edge neuroscience techniques to advance the medications development pipeline for SUDs.

The Opioid Crisis, Preventing and Managing Substance Abuse in India: A Systematic Review

The opioid crisis has emerged as a significant public health concern globally, with India facing unique challenges in preventing and managing substance abuse. This systematic review aims to analyze the current state of the opioid crisis in India, evaluate existing prevention and management strategies, and propose evidence-based recommendations for addressing this complex issue. A comprehensive literature search was conducted across multiple databases, resulting in the inclusion of 30 studies meeting the predefined criteria. The review highlights the multifaceted nature of the opioid crisis in India, influenced by factors such as socioeconomic conditions, cultural norms, and healthcare accessibility. Key findings include the need for comprehensive prevention programs, improved access to evidence-based treatments, and integration of harm reduction strategies. The review also emphasizes the importance of addressing co-occurring mental health disorders and the potential of community-based interventions in managing substance abuse. Challenges identified include stigma, limited access to treatment, inadequate healthcare infrastructure, regulatory barriers, and lack of comprehensive policies. Recommendations for future directions include developing culturally appropriate prevention programs, assessing the long-term effectiveness of treatment modalities, exploring innovative approaches to reduce stigma, and investigating the role of technology in improving access to care. By implementing a multifaceted approach that considers the unique sociocultural context of India (including factors such as family structures, religious beliefs, economic disparities, and regional variations in drug use patterns), there is potential to significantly reduce the burden of opioid abuse and improve outcomes for affected individuals and communities.

Perceptions of extended-release buprenorphine among people who received medication for opioid use disorder in jail: a qualitative study

BACKGROUND

Incarceration provides an opportunity for health interventions, including opioid use disorder (OUD) treatment and prevention of opioid-related overdoses post-release. All FDA-approved forms of medication for OUD (MOUD) treatment were mandated in several Massachusetts jails in 2019, with some jails offering extended-release buprenorphine (XR-Bup). Little is known about patient perspectives on and experiences with XR-Bup in carceral settings.

METHODS

We conducted semi-structured interviews in 2022 with community-dwelling people who received MOUD during a recent incarceration in a Massachusetts jail. We asked participants about their experiences with and perspectives on XR-Bup while in jail. Qualitative data were double-coded deductively and reviewed inductively to identify emergent themes, which were structured using the Theoretical Framework of Acceptability (TFA).

RESULTS

Participants (n = 38) had a mean age of 41.5 years, were 86% male, 84% White, 24% Hispanic, and 95% continued to receive MOUD at the time of their interview, including 11% receiving XR-Bup. Participants who viewed XR-Bup favorably appreciated avoiding the taste of sublingual buprenorphine; avoiding procedural difficulties and indignities associated with daily dosing in carceral settings (e.g., mouth checks, stigmatizing treatment from correctional staff); avoiding daily reminders of their addiction; experiencing less withdrawal; having extra time for other activities, such as work; and reduction of diversion of MOUD within the jail setting. Participants who viewed XR-Bup less favorably preferred to maintain their daily dosing routine; liked daily time out of their housing unit; wanted to know what was "going into my body everyday"; and feared needles and adverse events. Participants also reported that jail clinicians used XR-Bup for patients who were previously caught diverting sublingual buprenorphine, suggesting limited patient participation in decision-making around XR-Bup initiation in some jails.

CONCLUSION

People who received MOUD in Massachusetts jails had both favorable and unfavorable views and experiences with XR-Bup. Understanding these preferences can inform protocols in jails that are considering implementation of XR-Bup treatment.

Medial prefrontal neuroplasticity during extended-release naltrexone treatment of opioid use disorder - a longitudinal structural magnetic resonance imaging study

Opioid use disorder (OUD) has been linked to macroscopic structural alterations in the brain. The monthly injectable, extended-release formulation of μ-opioid antagonist naltrexone (XR-NTX) is highly effective in reducing opioid craving and preventing opioid relapse. Here, we investigated the neuroanatomical effects of XR-NTX by examining changes in cortical thickness during treatment for OUD. Forty-seven OUD patients underwent structural magnetic resonance imaging and subjectively rated their opioid craving ≤1 day before (pre-treatment) and 11 ± 3 days after (on-treatment) the first XR-NTX injection. A sample of fifty-six non-OUD individuals completed a single imaging session and served as the comparison group. A publicly available [¹¹C]carfentanil positron emission tomography dataset was used to assess the relationship between changes in cortical thickness and μ-opioid receptor (MOR) binding potential across brain regions. We found that the thickness of the medial prefrontal and anterior cingulate cortices (mPFC/aCC; regions with high MOR binding potential) was comparable between the non-OUD individuals and the OUD patients at pre-treatment. However, among the OUD patients, mPFC/aCC thickness significantly decreased from pre-treatment to on-treatment. A greater reduction in mPFC/aCC thickness was associated with a greater reduction in opioid craving. Taken together, our study suggests XR-NTX-induced cortical thickness reduction in the mPFC/aCC regions in OUD patients. The reduction in thickness does not appear to indicate a restoration to the non-OUD level but rather reflects XR-NTX's distinct therapeutic impact on an MOR-rich brain structure. Our findings highlight the neuroplastic effects of XR-NTX that may inform the development of novel OUD interventions.

A pilot randomized controlled trial of medication adherence therapy: Psychosocial leverage using a significant other (MAT-PLUS) for individuals on extended-release naltrexone

BACKGROUND

Extended-release naltrexone (XR-NTX) is an important treatment option for individuals with opioid use disorder (OUD) and/or alcohol use disorder (AUD). However, problems with retention are a major barrier to its overall effectiveness, and interventions to improve adherence are underdeveloped. The purpose of this study was to pilot test the MAT-PLUS intervention, which combines assertive outreach and involvement of a treatment significant other (TSO) to improve adherence to XR-NTX.

METHODS

Adults (N = 41) seeking treatment for OUD and/or AUD with XR-NTX were recruited from an inpatient addiction treatment center and randomized to the MAT-PLUS intervention or treatment as usual (TAU) for 16-weeks. TSOs (N = 19) of individuals in the MAT-PLUS condition were also enrolled. The primary outcome was the number of XR-NTX doses received and relapse to regular heavy use (opioid or alcohol) was a secondary outcome.

RESULTS

Participants in the MAT-PLUS group received 3.4 doses compared to 2.5 in TAU, which was significant after controlling for SUD diagnosis (p < 0.05). Rates of receipts of all prescribed doses were 61.1 % in MAT-PLUS compared to 30.4 % in TAU, giving an NNT of 3.3. Relapse rates and days of heavy use did not vary by treatment group.

CONCLUSIONS

This study demonstrates preliminary efficacy of the MAT-PLUS intervention for XR-NTX adherence. This study was limited by its small sample size and future research should broaden the intervention to apply across medications for SUD in larger samples. Family support with an emphasis on medication adherence has strong potential for improving addiction treatment outcomes.

Identifying facilitators and barriers to the uptake of medication for opioid use disorder in Washington, DC: A community-engaged concept mapping approach

INTRODUCTION

Opioid overdose is a major public health challenge. We aimed to understand facilitators and barriers to engagement in medication for opioid use disorder (MOUD) among persons with OUD in Washington, DC.

METHODS

We used a cross-sectional mixed-methods concept mapping approach to explore MOUD engagement between 2021-2022. Community members at-large generated 70 unique statements in response to the focus prompt: "What makes medication for opioid use disorder like buprenorphine (also known as Suboxone or Subutex) difficult to start or keep using?" Persons with OUD (n = 23) and service providers (n = 34) sorted and rated these statements by theme and importance. Data were analyzed with multidimensional scaling and hierarchical cluster analysis, producing thematic cluster maps. Results were validated by our community advisory board.

RESULTS

Seven themes emerged in response to the focus prompt: availability and accessibility; hopelessness and fear; unmet basic needs; characteristics of treatment programs; understanding and awareness of treatment; personal motivations, attitudes, and beliefs; and easier to use drugs. "Availability and accessibility," "hopelessness and fear," and "basic needs not being met" were the top three identified barriers to MOUD among consumers and providers; however, the order of these priorities differed between consumers and providers. There was a notable lack of communication and programming to address misconceptions about MOUD's efficacy, side effects, and cost. Stigma underscored many of the statements, showcasing its continued presence in clinical and social spaces.

CONCLUSIONS

This study distinguishes itself from other research on MOUD delivery and barriers by centering on community members and their lived experiences. Findings emphasize the need to expand access to treatment, dismantle stigma associated with substance use and MOUD, and address underlying circumstances that contribute to the profound sense of hopelessness and fear among persons with OUD-all of which will require collective action from consumers, providers, and the public.

Empirically contrasting urine drug screening-based opioid use disorder treatment outcome definitions

BACKGROUND AND AIMS

A lack of consensus on the optimal outcome measures to assess opioid use disorder (OUD) treatment efficacy and their precise definition and computation has hampered the pooling of research data for evidence synthesis and meta-analyses. This study aimed to empirically contrast multiple clinical trial definitions of treatment success by applying them to the same dataset.

METHODS

Data analysis used a suite of functions, developed as a software package for the R language, to operationalize 61 treatment outcome definitions based on urine drug screening (UDS) results. Outcome definitions were derived from clinical trials that are among the most influential in the OUD treatment field. Outcome functions were applied to a harmonized dataset from three large-scale National Drug Abuse Treatment Clinical Trials Network (CTN) studies, which tested various medication for OUD (MOUD) options (n = 2492). Hierarchical clustering was employed to empirically contrast outcome definitions.

RESULTS

The optimal number of clusters identified was three. Cluster 1, comprising eight definitions focused on detecting opioid-positive UDS, did not include missing UDS in outcome calculations, potentially resulting in inflated rates of treatment success. Cluster 2, with the highest variability, included 10 definitions characterized by strict criteria for treatment success, relying heavily on UDS results from either a brief period or a single study visit. The 43 definitions in Cluster 3 represented a diverse range of outcomes, conceptualized as measuring abstinence, use reduction and relapse. These definitions potentially offer more balanced measures of treatment success or failure, as they avoid the extreme methodologies characteristic of Clusters 1 and 2.

CONCLUSIONS

Clinical trials using urine drug screening (UDS) for objective substance use assessment in outcome definitions should consider (1) incorporating missing UDS data in outcome computation and (2) avoiding over-reliance on UDS data confined to a short time frame or the occurrence of a single positive urine test following a period of abstinence.

Neurobehavioral outcomes of infants exposed to buprenorphine-naloxone compared with naltrexone during pregnancy

BACKGROUND

Naltrexone is a medication used to treat both opioid and alcohol use disorder with limited experience in pregnant individuals, particularly in comparison to more commonly utilized treatments such as buprenorphine-naloxone. The long-term outcomes of infants exposed to naltrexone has not been previously examined.

AIMS

To compare the neurobehavioral outcomes of naltrexone versus buprenorphine-naloxone exposed infants.

STUDY DESIGN

Multi-centered prospective cohort study.

SUBJECTS

Pregnant people on prescribed buprenorphine-naloxone or naltrexone were enrolled during pregnancy and the dyad followed until 12 months after delivery.

OUTCOME MEASURES

Infants were evaluated at 4-6 weeks corrected gestational age (CGA) using the NICU Neonatal Neurobehavioral Scale (NNNS) and at the 12-month CGA visit using the Ages and Stages Questionnaire, Third Edition (ASQ-3).

RESULTS

There were 7 dyads in the naltrexone group and 34 in the buprenorphine-naloxone group. On the NNNS, infants exposed to naltrexone had higher median scores for arousal and excitability, and lower median scores for attention and regulation at 4-6 weeks CGA compared to the buprenorphine-naloxone group. None of the infants in the naltrexone group were monitored for NOWS and had shorter length of hospital stay compared with the buprenorphine-naloxone group. Although no statistically significant differences were observed, more infants in the buprenorphine-naloxone group were identified as at risk for development delays in the communication, problem solving, and personal social domains of the ASQ-3 at 12 months CGA. Results should be interpreted with caution given this study's small sample size and lack of a prospective comparison cohort.

CONCLUSIONS

In this small cohort, there are differences noted in infant neurobehavior by NNNS at 4-6 weeks of age when comparing the buprenorphine-naloxone and naltrexone groups. At 12 months, ASQ-3 scores were similar but with percentage differences in potential development delay risk observed between the two groups. Larger cohort studies are needed to determine the long-term child outcomes after naltrexone exposure in pregnancy.

Discontinuation of medication treatment for opioid use disorder after a successful course: The discontinuation phase of the CTN-0100 (RDD) trial

INTRODUCTION AND BACKGROUND

Buprenorphine, and extended-release naltrexone, are effective in decreasing opioid use, morbidity and mortality. The available evidence suggests that these medications should be used for long term treatment; however, patients often ask how long they need to be on medication, and whether it would be safe to discontinue. There are sparse data to guide us. The CTN-0100 trial will address this gap in our knowledge by studying participants who have decided to discontinue buprenorphine and extended-release naltrexone for OUD.

RESEARCH DESIGN AND METHODS

The trial is a multicenter, randomized, non-blinded study. Participants are stable adult volunteers, on sublingual buprenorphine, extended-release buprenorphine, or extended-release naltrexone, expressing an interest in discontinuing medication. Participants on buprenorphine must be stable for at least 1 year and participants on extended-release naltrexone must be stable for at least 6 months. Participants are engaged in the study for up to 96 weeks, including a flexible taper period, and are then transitioned to follow-up within the trial. All participants are randomly assigned to the study Medical Management (MM) or to MM plus Connections (CHESS health) digital smartphone application aimed at recovery and abstinence (MMD). Sublingual Buprenorphine participants are also randomized (2 × 2 design) to a taper using either sublingual or extended-release buprenorphine.

DISCUSSION/CONCLUSION

It is hoped that this trial will provide a rich source of data on management of patients discontinuing medication for opioid use disorder (MOUD) to inform future research and practice. The trial will shed light on which strategies are most likely to lead to long-term success (absence of relapse), and what participant characteristics distinguish those who can safely discontinue MOUD from those who remain at risk of relapse should they discontinue.

CLINICALTRIALS

gov Identifier: NCT04464980.

Target trial emulation for comparative effectiveness research with observational data: Promise and challenges for studying medications for opioid use disorder

Medications for opioid use disorder (MOUD) increase retention in care and decrease mortality during active treatment; however, information about the comparative effectiveness of different forms of MOUD is sparse. Observational comparative effectiveness studies are subject to many types of bias; a robust framework to minimize bias would improve the quality of comparative effectiveness evidence. This paper discusses the use of target trial emulation as a framework to conduct comparative effectiveness studies of MOUD with administrative data. Using examples from our planned research project comparing buprenorphine-naloxone and extended-release naltrexone with respect to the rates of MOUD discontinuation, we provide a primer on the challenges and approaches to employing target trial emulation in the study of MOUD.

Pregnancy Rates Among Women Treated with Medication for Opioid Use Disorder

BACKGROUND

Treatment-seeking people with opioid use disorder (OUD) who are capable of pregnancy need accurate information about the potential impact of medication to treat OUD (MOUD) on fertility to make informed choices about treatment that are consistent with their reproductive wishes. There is a dearth of research on fertility associated with MOUD receipt in birthing people with OUD.

OBJECTIVE

To estimate the association between treatment with MOUD and odds of conception among birthing people using national administrative claims.

DESIGN

Retrospective case-crossover study using multi-state US administrative data (2006-2016). Dates of conception were estimated from delivery dates and served as "case" days for which MOUD exposures were compared to those on all other ("control") days of insurance enrollment.

PARTICIPANTS

Treatment-seeking people with OUD with a delivery during the observation period.

MAIN MEASURES

Odds ratios for conception from within-person fixed effects models were modeled as a function of exposure to MOUD (buprenorphine, methadone, extended-release depot naltrexone, or oral naltrexone) using conditional logistic regression.

KEY RESULTS

A total of 21,928 births among 19,133 people with OUD were identified. In the sample, 5873 people received buprenorphine, 1825 methadone, 486 extended-release naltrexone, and 714 oral naltrexone. Participants could receive more than one type of MOUD. Mean age was 28.2 years (SD = 2.2; range = 16-45), with 76.2% having Medicaid. vs. commercial insurance. Compared to no MOUD, periods of methadone (aOR = 0.55 [95% CI = 0.48-0.63]) or buprenorphine receipt (aOR = 0.84 [0.77-0.91]) were associated with fewer conceptions. Treatment periods with extended-release depot naltrexone compared to no medication were associated with higher odds of conception (aOR = 1.75 [1.22-2.50]) and there was no significant difference in conception with oral naltrexone (aOR = 1.02 [0.67-1.54]).

CONCLUSIONS

The association between MOUD and odds of conception among birthing people varied by type of MOUD, with extended-release naltrexone associated with higher odds of conceiving compared to no treatment. Clinical studies are urgently needed to investigate these findings further.

Rapid Initiation of Injection Naltrexone for Opioid Use Disorder: A Stepped-Wedge Cluster Randomized Clinical Trial

Importance

Injectable extended-release (XR)-naltrexone is an effective treatment option for opioid use disorder (OUD), but the need to withdraw patients from opioid treatment prior to initiation is a barrier to implementation.

Objective

To compare the effectiveness of the standard procedure (SP) with the rapid procedure (RP) for XR-naltrexone initiation.

Design, Setting, and Participants

The Surmounting Withdrawal to Initiate Fast Treatment with Naltrexone study was an optimized stepped-wedge cluster randomized trial conducted at 6 community-based inpatient addiction treatment units. Units using the SP were randomly assigned at 14-week intervals to implement the RP. Participants admitted with OUD received the procedure the unit was delivering at the time of their admission. Participant recruitment took place between March 16, 2021, and July 18, 2022. The last visit was September 21, 2022.

Interventions

Standard procedure, based on the XR-naltrexone package insert (approximately 5-day buprenorphine taper followed by a 7- to 10-day opioid-free period and RP, defined as 1 day of buprenorphine at minimum necessary dose, 1 opioid-free day, and ascending low doses of oral naltrexone and adjunctive medications (eg, clonidine, clonazepam, antiemetics) for opioid withdrawal.

Main Outcomes and Measures

Receipt of XR-naltrexone injection prior to inpatient discharge (primary outcome). Secondary outcomes included opioid withdrawal scores and targeted safety events and serious adverse events. All analyses were intention-to-treat.

Results

A total of 415 participants with OUD were enrolled (mean [SD] age, 33.6 [8.48] years; 205 [49.4%] identified sex as male); 54 [13.0%] individuals identified as Black, 91 [21.9%] as Hispanic, 290 [69.9%] as White, and 22 [5.3%] as multiracial. Rates of successful initiation of XR-naltrexone among the RP group (141 of 225 [62.7%]) were noninferior to those of the SP group (68 of 190 [35.8%]) (odds ratio [OR], 3.60; 95% CI, 2.12-6.10). Withdrawal did not differ significantly between conditions (proportion of days with a moderate or greater maximum Clinical Opiate Withdrawal Scale score (>12) for RP vs SP: OR, 1.25; 95% CI, 0.62-2.50). Targeted safety events (RP: 12 [5.3%]; SP: 4 [2.1%]) and serious adverse events (RP: 15 [6.7%]; SP: 3 [1.6%]) were infrequent but occurred more often with RP than SP.

Conclusions and Relevance

In this trial, the RP of XR-naltrexone initiation was noninferior to the standard approach and saved time, although it required more intensive medical management and safety monitoring. The results of this trial suggest that rapid initiation could make XR-naltrexone a more viable treatment for patients with OUD.

Trial Registration

ClinicalTrials.gov Identifier: NCT04762537.

Case Series of Individuals Treated With Naltrexone During Pregnancy for Opioid and/or Alcohol Use Disorder

OBJECTIVE

There is a lack of knowledge about the relative safety and efficacy of naltrexone for the treatment of pregnant individuals with opioid and/or alcohol use disorder, including the range of outcomes, in both the pregnant individual and the infant, over the course of peripartum period. Our objective was to describe these outcomes in a cohort of pregnant individuals on naltrexone.

METHODS

In this prospective case series, 7 pregnant individuals with opioid use disorder (OUD) or alcohol use disorder (AUD) treated with naltrexone were followed from pregnancy through 12 months after delivery. Clinical treatment protocols and outcomes related to safety and efficacy during pregnancy, delivery, and the postpartum period are described.

RESULTS

There were 4 pregnant individuals with OUD and 3 with AUD, of which 3 were managed with oral and 4 with extended-release naltrexone. The mean gestational age at study enrollment was 21.7 (SD, 12) weeks. Of the 7 participants, there was no return to nonprescribed opioid use and 2 who experienced a return to alcohol use over the course of the study. All individuals delivered vaginally at a mean of 37 weeks gestation without any peripartum pain difficulties. Five of the individuals (71.4%) remained on naltrexone 12 months after delivery. There were no reported fetal anomalies and one preterm delivery. None of the infants developed neonatal opioid withdrawal syndrome.

CONCLUSIONS

For pregnant individuals with OUD or AUD treated with naltrexone, there were low rates of return to nonprescribed use and reassuring pregnant person and infant outcomes to 12 months postpartum.

The Effects of Chronic Naltrexone on Reinstatement of Opioid-Induced Drug-Seeking Behavior and Antinociception

Opioid addiction is a chronic relapsing disorder in which drug-seeking behavior during abstinence can be provoked by exposure to a µ-opioid receptor (MOR) agonist or opioid-associated cues. Opioid self-administration behavior in laboratory subjects can be reinstated by priming with MOR agonists or agonist-related stimuli, providing a procedure suitable for relapse-related studies. The opioid antagonist naltrexone has been forwarded as a medication that can forestall relapse and, in an extended-release formulation, has demonstrated some treatment success. However, chronic naltrexone treatment has not been extensively investigated in nonhuman subjects and aspects of its pharmacology remain uncertain. For example, the relative effectiveness of naltrexone in reducing the priming strength of opioid agonists differing in efficacy is not well understood. Here, using intravenous self-administration and warm-water tail withdrawal procedures, we investigated changes in the direct reinforcing effects of oxycodone and in the priming strength and antinociceptive effects of opioid agonists in squirrel monkeys (n = 4) during chronic treatment with naltrexone (0.2 mg/kg/d). Results show that naltrexone produced: 1) a 10-fold rightward shift in the dose-response function for the reinforcing effects of oxycodone, and 2) in reinstatement and antinociception experiments, comparable rightward shifts in the dose-response functions for higher-efficacy MOR agonists (methadone, heroin, and oxycodone) but rightward and downward shifts in the dose-response functions for lower-efficacy MOR agonists (buprenorphine, nalbuphine, and butorphanol). These results suggest that, although chronic naltrexone should be effective in forestalling relapse following exposure to lower- and higher-efficacy agonists, the inability of lower-efficacy agonists to surmount naltrexone antagonism may complicate the prescription of opioids for pain. SIGNIFICANCE STATEMENT: Although naltrexone is commonly used in the treatment of opioid use disorder, its ability to reduce the priming strength of opioid agonists has not been extensively investigated. This study shows that chronic naltrexone treatment induces rightward shifts in the reinstatement and antinociceptive properties of higher efficacy opioid agonists, but rightward and downward shifts for lower efficacy opioid agonists, suggesting lower efficacy agonists may not be able to surmount naltrexone-induced antagonism of these two effects, and perhaps naltrexone offers greater protection against lower efficacy agonists.

Clinical Implications of the Relationship Between Naltrexone Plasma Levels and the Subjective Effects of Heroin in Humans

BACKGROUND

Extended-release naltrexone (NTX) is an opioid antagonist approved for relapse prevention after medical withdrawal. Its therapeutic effect is dependent on the NTX plasma level, and as it decreases, patients may lack protection against relapse and overdose. Therefore, identifying the minimally effective NTX level needed to block opioid-induced subjective effects has important clinical implications.

METHODS

This secondary, individual-level analysis of data collected in a human laboratory study was conducted to evaluate the relationship between NTX levels and subjective effects of an intravenously administered 25-mg challenge dose of heroin in non-treatment-seeking participants with opioid use disorder (N = 12). Subjective ratings of drug liking using a 100-mm visual analog scale (VAS) and NTX levels were measured across 6 weeks after participants received a single injection of either extended-release NTX 192 mg (N = 6) or 384 mg (N = 6). Cubic spline mixed-effects models were used to provide 95% prediction intervals for individual changes in liking scores as a function of NTX levels.

RESULTS

Naltrexone levels above 2 ng/mL blocked nearly all VAS ratings of drug liking after intravenous heroin administration. Participants with NTX levels ≥ 2 ng/mL had minimal (≤20 mm) changes from placebo in VAS ratings of drug liking based on 95% prediction intervals. In contrast, NTX levels < 2 ng/mL were associated with greater variability in individual-level subjective responses.

CONCLUSIONS

In clinical practice, a plasma level range of 1 to 2 ng/mL is considered to be therapeutic in providing heroin blockade. The current findings suggest that a higher level (>2 ng/mL) may be needed to produce a consistent blockade.

Expanding access to medication treatment for opioid use disorders: Findings from the Washington State hub and spoke effort

BACKGROUND

Opioid use disorder (OUD) is a leading cause of preventable death and injury nationwide. Efforts to increase the use of medication for opioid use disorder (MOUD) are needed. In 2017, Washington State implemented a Hub and Spoke (HS) model of care with the primary goal of expanding access to MOUD. We examined changes in MOUD utilization among Washington State Medicaid beneficiaries before and after HS implementation.

METHODS

We used Medicaid claims data to examine longitudinal changes in MOUD use for beneficiaries with OUD. We conducted a comparative interrupted time series analysis to examine the association between HS policy implementation and rates of MOUD utilization, overall and by type of medication.

RESULTS

Between 2016 and 2019, a period of increasing OUD prevalence, rates of MOUD utilization among Washington Medicaid beneficiaries increased overall from 39.7 to 50.5. Following HS implementation, rates of MOUD use grew at a significantly greater rate in the HS cohort than in the non-HS cohort (β=0.54, SE=0.02, p< 0.0001, 95% CI 0.49, 0.59). Analyses by medication type show that this rate increase was primarily due to buprenorphine use (β= 0.61, SE= 0.02, p< 0.0001, 95% CI 0.57, 0.65).

CONCLUSION

Improved systems of care are needed to make MOUD accessible to all patients in need. The Washington HS model is one strategy that may facilitate and expand MOUD use, particularly buprenorphine. Over the study period, Washington State saw increased use of buprenorphine, which was an emphasis of their HS model.

Novel Therapeutic and Program-Based Approaches to Opioid Use Disorders

Opioid use disorder continues to drive overdose deaths in many countries, including the United States. Illicit fentanyl and its analogues have emerged as key contributors to the complications and mortality associated with opioid use disorder. Medications for opioid use disorder treatment, such as methadone and buprenorphine, are safe and substantially reduce opioid use, infectious complications, and mortality risk, but remain underutilized. Polysubstance use and emerging substances such as xylazine and designer benzodiazepines create additional treatment challenges. Recent clinical and policy innovations in treatment delivery, including telemedicine, bridge clinics, and expanded models for accessing methadone have the potential to increase access to life-saving care for people living with opioid use disorder.

IUPHAR review: Recent progress in the development of Mu opioid receptor modulators to treat opioid use disorders

Opioid Use Disorder (OUD) can be described as intense preoccupation with using or obtaining opioids despite the negative consequences associated with their use. As the number of OUD cases in the U.S. increase, so do the number of opioid-related overdose deaths. In 2022, opioid-related overdose became the No. 1 cause of death for individuals in the U.S. between the ages of 25 and 64 years of age. Because of the introduction of highly potent synthetic opioids (e.g. fentanyl) to the illicit drug market, there is an urgent need for therapeutics that successfully reduce the number of overdoses and can help OUD patients maintain sobriety. Most abused opioids stimulate the mu-opioid receptor (MOR) and activation of this receptor can lead to positive (e.g., euphoria) consequences. However, the negative side effects of MOR stimulation can be fatal (e.g., sedation, respiratory depression). Therefore, the MOR is an attractive target for developing medications to treat OUD. Current FDA drugs include MOR agonists that aid in detoxification and relapse prevention, and MOR antagonists that also serve as maintenance therapies or reverse overdose. These medications are limited by their abuse potential, adverse effects, or pharmacological profiles which leaves ample room for research into designing new chemical entities with optimal physiological effects. These includes, orthosteric ligands that target the primary binding site of the MOR, allosteric ligands that positively, negatively, or "silently" modulate receptor function, and lastly, bitopic ligands target both the orthosteric and allosteric sites simultaneously.

Non-prescribing clinicians' treatment orientations and attitudes toward treatments for opioid use disorder: Rural differences

INTRODUCTION

The United States has experienced substantial increases in opioid use for more than two decades. This growth has impacted rural areas where overdoses have risen drastically during this time period and more often involve prescription opioids than in urban areas. Medications for opioid use disorders (MOUDs) are highly underutilized in rural settings due to lack of access, inadequate prescribing, and stigma.

METHODS

The study collected data using a cross-sectional online survey of nonprescribing clinicians (NPCs) involved in the treatment of substance use disorders (SUDs) in the United States. The study used multiple recruitment methods to obtain a purposive sample of NPCs from a variety of geographical contexts across the nation. The survey assessed demographic and practice characteristics including rurality of practice location, exposure and training related to MOUDs, treatment orientation, treatment preferences for opioid use disorder (OUD), and attitudes toward MOUDs. The study compared treatment preferences for OUD and attitudes toward MOUDs based on rurality of practice location. We tested a mediation model to determine whether the relationship between rurality of practice setting and attitudes toward MOUDs is mediated by treatment orientation.

RESULTS

Most of the 636 NPCs surveyed favored a combination of MOUDs and psychosocial treatment. Compared to clinicians practicing in suburban or urban areas, self-identified rural clinicians were more likely to favor MOUDs alone as most effective and less likely to endorse a combination of MOUDs and psychosocial treatment. Although most NPCs were supportive of MOUDs overall, many endorsed misconceptions related to MOUDs. Rural clinicians were less likely to perceive MOUDs as effective or acceptable compared to those in urban settings. Results of a mediation analysis indicated that practicing in a rural location compared to in an urban location directly and indirectly influenced attitudes toward MOUDs through an effect on treatment orientation.

CONCLUSIONS

NPCs play important roles in the implementation of MOUDs, and while efforts to increase their knowledge of and exposure to MOUDs have contributed broadly to more favorable attitudes toward MOUDs among NPCs, this study's findings indicate that additional efforts are still needed, particularly among NPCs who work in rural settings. Findings also indicate that, among rural clinicians, increasing knowledge of and exposure to harm reduction principles may be a necessary prerequisite to engaging them in the implementation of specific harm reduction strategies such as MOUDs.

Implementing harm reduction kits in an office-based addiction treatment program

BACKGROUND

The rising rates of drug use-related complications call for a paradigm shift in the care for people who use drugs. While addiction treatment and harm reduction have historically been siloed in the US, co-location of these services in office-based addiction treatment (OBAT) settings offers a more realistic and patient-centered approach. We describe a quality improvement program on integrating harm reduction kits into an urban OBAT clinic.

METHODS

After engaging appropriate stakeholders and delivering clinician and staff trainings on safer use best practices, we developed a clinical workflow for universal offering and distribution of pre-packaged kits coupled with patient-facing educational handouts. We assessed: (1) kit uptake with kit number and types distributed; and (2) implementation outcomes of feasibility, acceptability, appropriateness, and patient perceptions.

RESULTS

One-month post-implementation, 28% (40/141) of completed in-person visits had at least one kit request, and a total of 121 kits were distributed. Staff and clinicians found the program to be highly feasible, acceptable, and appropriate, and patient perceptions were positive.

CONCLUSIONS

Incorporating kits in OBAT settings is an important step toward increasing patient access and utilization of life-saving services. Our program uncovered a significant unmet need among our patients, suggesting that kit integration within addiction treatment can improve the standard of care for people who use drugs.

Guideline No. 443a: Opioid Use Throughout Women's Lifespan: Fertility, Contraception, Chronic Pain, and Menopause

OBJECTIVE

To provide health care providers with the best evidence on opioid use and women's health. Areas of focus include general patterns of opioid use and safety of use; care of women who use opioids; stigma, screening, brief intervention, and referral to treatment; hormonal regulation; reproductive health, including contraception and fertility; sexual function; perimenopausal and menopausal symptoms; and chronic pelvic pain syndromes.

TARGET POPULATION

The target population includes all women currently using or contemplating using opioids.

OUTCOMES

Open, evidence-informed dialogue about opioid use will lead to improvements in patient care and overall health.

BENEFITS, HARMS, AND COSTS

Exploring opioid use through a trauma-informed approach offers the health care provider and patient with an opportunity to build a strong, collaborative, and therapeutic alliance. This alliance empowers women to make informed choices about their own care. It also allows for the diagnosis and possible treatment of opioid use disorders. Use should not be stigmatized, as stigma leads to poor "partnered care" (i.e., the partnership between the patient and care provider). Therefore, health care providers and patients must understand the potential role of opioids in women's health (both positive and negative) to ensure informed decision-making.

EVIDENCE

A literature search was designed and carried out in PubMed and the Cochrane Library databases from August 2018 until March 2023 using following MeSH terms and keywords (and variants): opioids, illicit drugs, fertility, pregnancy, breastfeeding, and aging.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).

INTENDED AUDIENCE

All health care providers who care for women.

TWEETABLE ABSTRACT

Opioid use can affect female reproductive function; health care providers and patients must understand the potential role of opioids in women's health to ensure informed decision-making.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Implementing contingency management for stimulant use in opioid treatment programs: protocol of a type III hybrid effectiveness-stepped-wedge trial

BACKGROUND

Contingency management (CM) is an evidence-based intervention for stimulant use and is highly effective in combination with medication for opioid use disorder. Yet, uptake of CM in opioid treatment programs that provide medication for opioid use disorder remains low. This paradox in which CM is one of the most effective interventions, yet one of the least available, represents one of the greatest research-to-practice gaps in the addiction health services field. Multi-level implementation strategies are needed to address barriers to CM implementation at both the provider- and organization-level. This type III hybrid effectiveness-implementation trial was funded by the National Institute on Drug Abuse to evaluate whether a multi-level implementation strategy, the Science of Service Laboratory (SSL), can effectively promote CM implementation in opioid treatment programs. Specific aims will test the effectiveness of the SSL on implementation outcomes (primary aim) and patient outcomes (secondary aim), as well as test putative mediators of implementation outcomes (exploratory aim).

METHODS

Utilizing a fully powered type III hybrid effectiveness-implementation trial with a stepped wedge design, we propose to randomize a cohort of 10 opioid treatment programs to receive the SSL across four steps. Each step, an additional 2-3 opioid treatment programs will receive the SSL implementation strategy, which has three core components: didactic training, performance feedback, and external facilitation. At six intervals, each of the 10 opioid treatment programs will provide de-identified electronic medical record data from all available patient charts on CM delivery and patient outcomes. Staff from each opioid treatment program will provide feedback on contextual determinants influencing implementation at three timepoints.

DISCUSSION

Between planning of this protocol and receipt of funding, the landscape for CM in the USA changed dramatically, with multiple Departments of Health launching state-wide CM initiatives. We therefore accelerated the protocol timeline and offered some cursory training resources to all sites as a preparation activity. We also began partnering with multiple Departments of Health to evaluate their rollout of CM using the measures outlined in this protocol.

TRIAL REGISTRATION

This study protocol is registered via ClinicalTrials.gov Identifier: NCT05702021. Date of registration: January 27, 2023.

Caring for Our Patients With Opioid Use Disorder in the Perioperative Period: A Guide for the Anesthesiologist

Opioid use disorder (OUD) is a rising public health crisis, impacting millions of individuals and families worldwide. Anesthesiologists can play a key role in improving morbidity and mortality around the time of surgery by informing perioperative teams and guiding evidence-based care and access to life-saving treatment for patients with active OUD or in recovery. This article serves as an educational resource for the anesthesiologist caring for patients with OUD and is the second in a series of articles published in Anesthesia & Analgesia on the anesthetic and analgesic management of patients with substance use disorders. The article is divided into 4 sections: (1) background to OUD, treatment principles, and the anesthesiologist; (2) perioperative considerations for patients prescribed medications for OUD (MOUD); (3) perioperative considerations for patients with active, untreated OUD; and (4) nonopioid and nonpharmacologic principles of multimodal perioperative pain management for patients with untreated, active OUD, or in recovery. The article concludes with a stepwise approach for the anesthesiologist to support OUD treatment and recovery. The anesthesiologist is an important leader of the perioperative team to promote these suggested best practices and help save lives.

"They Talk to Me Like a Person" Experiences of People in an Injectable Opioid Agonist Treatment Program: A Qualitative Interpretive Description

OBJECTIVE

The aim of this study was to explore client experiences in a community-based injectable opioid agonist therapy (iOAT) program.

STUDY SETTING

The study occurred across two cities in Alberta, Canada.

STUDY DESIGN

The research team conducted secondary interpretive description analysis on qualitative interview transcripts.

DATA COLLECTION

Twenty-three iOAT clients were interviewed as part of a prior quality improvement initiative. Using secondary analysis of the transcripts, interviews were analyzed for themes, to create an understanding of clients' experiences.

PRINCIPAL FINDINGS

Participants accessed iOAT through other health services, for treatment of opioid use disorder. Participants reported that building trusting and supportive relationships with nurses was crucial to their success in the program. Through these relationships, participants experienced stopping and starting. They stopped behaviors such as illicit drug use, having withdrawal symptoms and anxiety, and prohibited income generation activities. They started taking care of themselves, accessing housing, increasing financial stability, receiving primary care, and connecting with friends and family. The global experience of iOAT was one of positive change for participants.

CONCLUSIONS

The findings of this study are largely consistent with other published examples-iOAT programs create benefits for both clients and their communities. Although clients may join the program to access the hydromorphone, the relationships between staff and clients are the key driver of success.

Evaluation of the New England Office Based Addiction Treatment ECHO: A Tool for Strengthening the Addiction Workforce

INTRODUCTION

Reducing substance-related morbidity requires an educated and well-supported workforce. The New England Office Based Addiction Treatment Extension for Community Healthcare Outcomes (NE OBAT ECHO) began in 2019 to support community-based addiction care teams through virtual mentoring and case-based learning. We sought to characterize the program's impact on the knowledge and attitudes of NE OBAT ECHO participants.

METHODS

We conducted an 18-month prospective evaluation of the NE OBAT ECHO. Participants registered for 1 of 2 successive ECHO clinics. Each 5-month clinic included ten 1.5-hour sessions involving brief didactic lectures and de-identified patient case presentations. Participants completed surveys at Month-0, -6, -12, and -18 to assess attitudes about working with patients who use drugs and evidence based practices (EBPs), stigma toward people who use drugs, and addiction treatment knowledge. We compared outcomes using 2 approaches: (i) between-groups, which involved comparing the first intervention group to the delayed intervention (comparison) group, and (ii) within-groups, which involved comparing outcomes at different time points for all participants. In the within-group approach, each participant acted as their own control.

RESULTS

Seventy-six health professionals participated in the NE OBAT ECHO, representing various roles in addiction care teams. Approximately half (47% [36/76]) practiced primary care, internal, or family medicine. The first intervention group reported improved job satisfaction and openness toward EBPs compared to the delayed intervention group. Within-group analyses revealed that ECHO participation was associated with increased positive perceptions of role adequacy, support, legitimacy, and satisfaction 6 months following program completion. No changes were identified in willingness to adopt EBPs or treatment knowledge. Stigma toward people who use drugs was persistent in both groups across time points.

CONCLUSIONS

NE OBAT ECHO may have improved participants' confidence and satisfaction providing addiction care. ECHO is likely an effective educational tool for expanding the capacity of the addiction workforce.

Personal recovery among people with opioid use disorder during treatment with extended-release naltrexone

Background and aims

Recovery from substance use disorders (SUD) has traditionally been equated with abstinence. "Personal recovery" however emphasizes recovery as a unique and personal process, supported by changes in connectedness, hope, identity, meaning and empowerment. This study aimed to examine personal recovery in people receiving extended-release naltrexone (XR-NTX); specifically investigate changes in personal recovery during treatment, identify groups of participants following distinct trajectories of recovery, and characteristics predicting group-belonging.

Methods

Overall change in recovery (Questionnaire about the Process of Recovery, QPR) score was assessed by linear mixed model in a subsample of 135 people with opioid use disorder (OUD) participating in a 24 + 28-week trial of XR-NTX. Growth mixture model was used to identify potential groups of people following distinct trajectories of personal recovery.

Results

Overall, there was a significant change in QPR score during treatment. Four groups with distinct recovery trajectories were identified: "initially low- increase" (G1), "initially average- no change" (G2), "initially high- no change" (G3) and "initially high- increase" (G4). The groups were different with regards to level of psychological distress, social support, and the use of benzodiazepines. In addition, previous participation in opioid agonist treatment programs, current pain, life satisfaction, employment, heroin craving and previous use of heroin also differed between groups.

Conclusions

Personal recovery among people receiving XR-NTX follows different trajectories, and various factors are associated with personal recovery. Particular attention regarding psychological distress, social support and heroin use among patients commencing XR-NTX treatment is important to facilitate successful recovery trajectories.

Targeting Opioid Receptors in Addiction and Drug Withdrawal: Where Are We Going?

This review article offers an outlook on the use of opioids as therapeutics for treating several diseases, including cancer and non-cancer pain, and focuses the analysis on the opportunity to target opioid receptors for treating opioid use disorder (OUD), drug withdrawal, and addiction. Unfortunately, as has been well established, the use of opioids presents a plethora of side effects, such as tolerance and physical and physiological dependence. Accordingly, considering the great pharmacological potential in targeting opioid receptors, the identification of opioid receptor ligands devoid of most of the adverse effects exhibited by current therapeutic agents is highly necessary. To this end, herein, we analyze some interesting molecules that could potentially be useful for treating OUD, with an in-depth analysis regarding in vivo studies and clinical trials.

Invited Commentary: On the Mathematization of Epidemiology as a Socially Engaged Quantitative Science

Ensuring that patients with opioid use disorder (OUD) have access to optimal medication therapies is a critical challenge in substance use epidemiology. Rudolph et al. (Am J Epidemiol. 2023;XXX(X):XXXX-XXXX) demonstrated that sophisticated data-adaptive statistical techniques can be used to learn optimal, individualized treatment rules that can aid providers in choosing a medication treatment modality for a particular patient with OUD. This important work also highlights the effects of the mathematization of epidemiologic research. Here, we define mathematization and demonstrate how it operates in the context of effectiveness research on medications for OUD using the paper by Rudolph et al. as a springboard. In particular, we address the normative dimension of mathematization and how it tends to resolve a fundamental tension in epidemiologic practice between technical sophistication and public health considerations in favor of more technical solutions. The process of mathematization is a fundamental part of epidemiology; we argue not for eliminating it but for balancing mathematization and technical demands equally with practical and community-centric public health needs.

Extended-release Naltrexone Is Not Linked to Hepatotoxicity in Adults Experiencing Homelessness and Alcohol Use Disorder

OBJECTIVES

The use of extended-release naltrexone (XR-NTX) as treatment for alcohol use disorder (AUD) has been limited by a prior black box warning for hepatotoxicity. We performed a secondary analysis of data from a randomized clinical trial to compare serum liver enzyme levels for those randomized to XR-NTX versus placebo.

METHODS

The parent study aimed to test the efficacy of combined pharmacobehavioral harm-reduction treatment in improving alcohol and quality-of-life outcomes for adults experiencing homelessness and AUD. We compared the 2 arms that received intramuscular injections of either 380 mg XR-NTX (n = 74) or placebo (n = 77). Outcomes included ( a ) liver enzyme levels and ( b ) liver enzyme values categorized as normal (<1× upper limit of normal [ULN]), elevated (1-3× ULN), or high (>3× ULN). We performed multinomial logistic regression and negative binomial generalized estimating equations modeling to assess the effects of treatment group and the time × treatment group interaction on liver enzyme outcomes.

RESULTS

The mean age was 47.9 ± 9.9 years, and the mean baseline alcohol consumption was 23.2 ± 14.0 drinks per day. There were no significant differences in the development of liver enzyme elevations 1 to 3× ULN or more than 3× ULN (all P s > 0.25) or in the change in liver enzyme values (all P s > 0.41) between the placebo and the XR-NTX groups over the treatment course.

CONCLUSIONS

In our study of adults experiencing homelessness and AUD, receipt of XR-NTX was not associated with hepatotoxicity. These findings support the use of XR-NTX to treat AUD even in patients who are drinking heavily and physiologically dependent on alcohol.

Duration of medication treatment for opioid-use disorder and risk of overdose among Medicaid enrollees in 11 states: a retrospective cohort study

BACKGROUND AND AIMS

Medication for opioid use disorder (MOUD) reduces harms associated with opioid use disorder (OUD), including risk of overdose. Understanding how variation in MOUD duration influences overdose risk is important as health-care payers increasingly remove barriers to treatment continuation (e.g. prior authorization). This study measured the association between MOUD continuation, relative to discontinuation, and opioid-related overdose among Medicaid beneficiaries.

DESIGN

Retrospective cohort study using landmark survival analysis. We estimated the association between treatment continuation and overdose risk at 5 points after the index, or first, MOUD claim. Censoring events included death and disenrollment.

SETTING AND PARTICIPANTS

Medicaid programs in 11 US states: Delaware, Kentucky, Maryland, Maine, Michigan, North Carolina, Ohio, Pennsylvania, Virginia, West Virginia and Wisconsin. A total of 293 180 Medicaid beneficiaries aged 18-64 years with a diagnosis of OUD and had a first MOUD claim between 2016 and 2017.

MEASUREMENTS

MOUD formulations included methadone, buprenorphine and naltrexone. We measured medically treated opioid-related overdose within claims within 12 months of the index MOUD claim.

FINDINGS

Results were consistent across states. In pooled results, 5.1% of beneficiaries had an overdose, and 67% discontinued MOUD before an overdose or censoring event within 12 months. Beneficiaries who continued MOUD beyond 60 days had a lower relative overdose hazard ratio (HR) compared with those who discontinued by day 60 [HR = 0.39; 95% confidence interval (CI) = 0.36-0.42; P < 0.0001]. MOUD continuation was associated with lower overdose risk at 120 days (HR = 0.34; 95% CI = 0.31-0.37; P < 0.0001), 180 days (HR = 0.31; 95% CI = 0.29-0.34; P < 0.0001), 240 days (HR = 0.29; 95% CI = 0.26-0.31; P < 0.0001) and 300 days (HR = 0.28; 95% CI = 0.24-0.32; P < 0.0001). The hazard of overdose was 10% lower with each additional 60 days of MOUD (95% CI = 0.88-0.92; P < 0.0001).

CONCLUSIONS

Continuation of medication for opioid use disorder (MOUD) in US Medicaid beneficiaries was associated with a substantial reduction in overdose risk up to 12 months after the first claim for MOUD.

Medication for opioid use disorder treatment continuity post-release from jail: A qualitative study with community-based treatment providers

BACKGROUND

People released from jail are at elevated opioid overdose risk. Medications for opioid use disorder (MOUD) are effective in reducing overdoses. MOUD treatment was recently mandated in seven Massachusetts jails, but little is known about barriers and facilitators to treatment continuity post-release. We aimed to assess MOUD provider perspectives on treatment continuity among people released from jail.

METHODS

We conducted qualitative interviews with 36 medical, supervisory, and administrative staff at MOUD programs that serve jail-referred patients. We used the Exploration, Preparation, Implementation, and Sustainment (EPIS) implementation science framework to guide development of instruments, codes, and analyses. We employed deductive and inductive coding, and a grounded theory analytical approach to identify salient themes.

RESULTS

Inner context findings highlighted necessary adjustments among jail staff to approve MOUD treatment, especially with agonist medications that were previously considered contraband. Participants perceived that some staff within jails favored abstinence-based recovery, viewing agonists as a crutch. Bridging results highlighted the importance of inter-agency communication and coordination to ensure information transfer for seamless treatment continuity in the community post-release. Pre-release planning, release on pre-scheduled dates, medication provision to cover gaps between jail release and intake at community MOUD sites, and exchange of treatment information across agencies were viewed as paramount to success. Unexpected early releases and releases from court were viewed as barriers to treatment coordination. Outer context domains were largely tied to social determinants of health. Substantial barriers to treatment continuity included shelter, food security, employment, transportation, and insurance reactivation.

CONCLUSION

Through qualitative interviews with community-based MOUD staff, we identified salient barriers and facilitators to treatment continuity post-release from jails. Findings point to needed investments in care coordination, staffing, and funding to strengthen jail-to-community-based MOUD treatment, removing barriers to continuity, and decreasing opioid overdose deaths during this high-risk transition.

Sleep disturbance as a therapeutic target to improve opioid use disorder treatment

Sleep health is an important factor across several physical and mental health disorders, and a growing scientific consensus has identified sleep as a critical component of opioid use disorder (OUD), both in the active disease state and during OUD recovery. The goal of this narrative review is to collate the literature on sleep, opioid use, and OUD as a means of identifying therapeutic targets to improve OUD treatment outcomes. Sleep disturbance is common and often severe in persons with OUD, especially during opioid withdrawal, but also in persons on opioid maintenance therapies. There is ample evidence that sleep disturbances including reduced total sleep time, disrupted sleep continuity, and poor sleep quality often accompany negative OUD treatment outcomes. Sleep disturbances are bidirectionally associated with several other factors related to negative treatment outcomes, including chronic stress, stress reactivity, low positive affect, high negative affect, chronic pain, and drug craving. This constellation of outcome variables represents a more comprehensive appraisal of the quality of life and quality of recovery than is typically assessed in OUD clinical trials. To date, there are very few clinical trials or experimental studies aimed at improving sleep health in OUD patients, either as a means of improving stress, affect, and craving outcomes, or as a potential mechanistic target to reduce opioid withdrawal and drug use behaviors. As such, the direct impact of sleep improvement in OUD patients is largely unknown, yet mechanistic and clinical research suggests that therapeutic interventions that target sleep are a promising avenue to improve OUD treatment. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Pain is reduced by transcutaneous cervical vagus nerve stimulation and correlated with cardiorespiratory variability measures in the context of opioid withdrawal

Over 100,000 individuals in the United States lost their lives secondary to drug overdose in 2021, with opioid use disorder (OUD) being a leading cause. Pain is an important component of opioid withdrawal, which can complicate recovery from OUD. This study's objectives were to assess the effects of transcutaneous cervical vagus nerve stimulation (tcVNS), a technique shown to reduce sympathetic arousal in other populations, on pain during acute opioid withdrawal and to study pain's relationships with objective cardiorespiratory markers. Twenty patients with OUD underwent opioid withdrawal while participating in a two-hour protocol. The protocol involved opioid cues to induce opioid craving and neutral conditions for control purposes. Adhering to a double-blind design, patients were randomly assigned to receive active tcVNS (n = 9) or sham stimulation (n = 11) throughout the protocol. At the beginning and end of the protocol, patients' pain levels were assessed using the numerical rating scale (0-10 scale) for pain (NRS Pain). During the protocol, electrocardiogram and respiratory effort signals were measured, from which heart rate variability (HRV) and respiration pattern variability (RPV) were extracted. Pre- to post- changes (denoted with a Δ) were computed for all measures. Δ NRS Pain scores were lower (P = 0.045) for the active group (mean ± standard deviation: -0.8 ± 2.4) compared to the sham group (0.9 ± 1.0). A positive correlation existed between Δ NRS pain scores and Δ RPV (Spearman's ρ = 0.46; P = 0.04). Following adjustment for device group, a negative correlation existed between Δ HRV and Δ NRS Pain (Spearman's ρ = -0.43; P = 0.04). This randomized, double-blind, sham-controlled pilot study provides the first evidence of tcVNS-induced reductions in pain in patients with OUD experiencing opioid withdrawal. This study also provides the first quantitative evidence of an association between breathing irregularity and pain. The correlations between changes in pain and changes in objective physiological markers add validity to the data. Given the clinical importance of reducing pain non-pharmacologically, the findings support the need for further investigation of tcVNS and wearable cardiorespiratory sensing for pain monitoring and management in patients with OUD.

CDC Clinical Practice Guideline for Prescribing Opioids for Pain - United States, 2022

This guideline provides recommendations for clinicians providing pain care, including those prescribing opioids, for outpatients aged ≥18 years. It updates the CDC Guideline for Prescribing Opioids for Chronic Pain - United States, 2016 (MMWR Recomm Rep 2016;65[No. RR-1]:1-49) and includes recommendations for managing acute (duration of <1 month), subacute (duration of 1-3 months), and chronic (duration of >3 months) pain. The recommendations do not apply to pain related to sickle cell disease or cancer or to patients receiving palliative or end-of-life care. The guideline addresses the following four areas: 1) determining whether or not to initiate opioids for pain, 2) selecting opioids and determining opioid dosages, 3) deciding duration of initial opioid prescription and conducting follow-up, and 4) assessing risk and addressing potential harms of opioid use. CDC developed the guideline using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework. Recommendations are based on systematic reviews of the scientific evidence and reflect considerations of benefits and harms, patient and clinician values and preferences, and resource allocation. CDC obtained input from the Board of Scientific Counselors of the National Center for Injury Prevention and Control (a federally chartered advisory committee), the public, and peer reviewers. CDC recommends that persons with pain receive appropriate pain treatment, with careful consideration of the benefits and risks of all treatment options in the context of the patient's circumstances. Recommendations should not be applied as inflexible standards of care across patient populations. This clinical practice guideline is intended to improve communication between clinicians and patients about the benefits and risks of pain treatments, including opioid therapy; improve the effectiveness and safety of pain treatment; mitigate pain; improve function and quality of life for patients with pain; and reduce risks associated with opioid pain therapy, including opioid use disorder, overdose, and death.

Advancing Pharmacological Treatments for Opioid Use Disorder (ADaPT-OUD): an Implementation Trial in Eight Veterans Health Administration Facilities

BACKGROUND

Identifying effective strategies to improve access to medication treatments for opioid use disorder (MOUD) is imperative. Within the Veterans Health Administration (VHA), provision of MOUD varies significantly, requiring development and testing of implementation strategies that target facilities with low provision of MOUD.

OBJECTIVE

Determine the effectiveness of external facilitation in increasing the provision of MOUD among VHA facilities with low baseline provision of MOUD compared to matched controls.

DESIGN

Pre-post, block randomized study designed to compare facility-level outcomes in a stratified sample of eligible facilities. Four blocks (two intervention facilities in each) were defined by median splits of both the ratio of patients with OUD receiving MOUD and number of patients with OUD not currently receiving MOUD (i.e., number of actionable patients). Intervention facilities participated in a 12-month implementation intervention.

PARTICIPANTS

VHA facilities in the lowest quartile of MOUD provision (35 facilities), eight of which were randomly assigned to participate in the intervention (two per block) with twenty-seven serving as matched controls by block.

INTERVENTION

External facilitation included assessment of local barriers/facilitators, formation of a local implementation team, a site visit for action planning and training/education, cross-facility quarterly calls, monthly coaching calls, and consultation.

MAIN MEASURES

Pre- to post-change in the facility-level ratio of patients with an OUD diagnosis receiving MOUD compared to control facilities.

KEY RESULTS

Intervention facilities significantly increased the ratio of patients with OUD receiving MOUD from an average of 18% at baseline to 30% 1 year later, with an absolute difference of 12% (95% confidence interval [CI]: 6.6%, 17.0%). The difference in differences between intervention and control facilities was 3.0% (95% CI: - 0.2%. 6.7%). The impact of the intervention varied by block, with smaller, less complex facilities more likely to outperform matched controls.

CONCLUSIONS

Intensive external facilitation improved the adoption of MOUD in most low-performing facilities and may enhance adoption beyond other interventions less tailored to individual facility contexts.

Maintenance on extended-release naltrexone is associated with reduced injection opioid use among justice-involved persons with opioid use disorder

INTRODUCTION

Opioid use disorder (OUD) and injection drug use (IDU) place justice-involved individuals at increased risk for acquiring or transmitting HIV or hepatitis C virus (HCV). Methadone and buprenorphine have been associated with reduced opioid IDU; however, the effect of extended-release naltrexone (XR-NTX) on this behavior is incompletely studied.

METHODS

This study examined injection opioid use and shared injection equipment behavior from a completed double-blind placebo-controlled trial of XR-NTX among 88 justice-involved participants with HIV and OUD. Changes in participants' self-reported daily injection opioid use and shared injection equipment was evaluated pre-incarceration, during incarceration, and monthly post-release for 6 months. The study also assessed differences in time to first opioid injection post-release. The research team performed intention to treat and "as treated" (high treatment versus low treatment) analyses.

RESULTS

Fifty-eight of 88 participants (69.5 %) endorsed IDU and 26 (29.5 %) reported sharing injection equipment in the 30 days pre-incarceration; 2 participants (2.2 %) reported IDU during incarceration; 19 (21.6 %) reported IDU one month post-release from prison or jail. Fifty-four (61.4 %) participants had an HIV RNA below 200 copies/mL and 62 (70.5 %) were baseline HCV antibody positive. The 6-month follow-up rate was 49.5 % and 50.5 % for those who received XR-NTX and placebo, respectively, which was not significantly different (p = 0.822). Participants in the XR-NTX and placebo groups had similar low mean opioid injection use post-release and time to first injection opioid use in the Intention-to-treat analysis. In the as-treated analysis, participants in the high treatment group had significantly lower mean proportion of days injecting opioids (13.8 % high treatment versus 22.8 % low treatment, p = 0.02) by month 1, which persisted up to 5 months post-release (0 % high treatment vs 24.3 % low treatment, p < 0.001) and experienced a longer time to first opioid injection post-release (143.8 days high treatment vs 67.4 days low treatment, p < 0.001).

CONCLUSIONS

Injection opioid use was low during incarceration and remained low post-release in this justice-involved population. Retention on XR-NTX was associated with reduced intravenous opioid use, which has important implications for reducing transmission of HIV and HCV.

Cost-effectiveness of extended-release injectable naltrexone among incarcerated persons with opioid use disorder before release from prison versus after release

INTRODUCTION

Opioid use disorder (OUD) is highly prevalent among incarcerated populations, and the risk of fatal overdose following release from prison is substantial. Despite efficacy, few correctional facilities provide evidence-based addiction treatment. Extended-release injectable naltrexone (XR-NTX) administered prior to release from incarceration may improve health and economic outcomes.

METHODS

We conducted an economic evaluation alongside a randomized controlled trial testing the effectiveness of XR-NTX before release from prison (n = 38) vs. XR-NTX referral after release (n = 48) of incarcerated participants with OUD, both groups continuing treatment at a community addiction treatment center. The incremental cost-effectiveness ratio (ICER) assessed the cost-effectiveness of XR-NTX before release compared to referral after release for three stakeholder perspectives at 12- and 24-week periods: state policymaker, health care sector, and societal. Effectiveness measures included quality-adjusted life-years (QALYs) and abstinent years from opioids. In addition, we categorized resources as OUD-related and non-OUD-related medical care, state transfer payments, and other societal costs (productivity, criminal justice resources, etc.).

RESULTS

Results showed an association between XR-NTX and greater OUD-related costs and total costs from the state policymaker perspective. QALYs gained were positive but statistically insignificant between arms; however, results showed XR-NTX had an estimated 15.5 more days of opioid abstinence over 24 weeks and statistically significant at a 95 % confidence level based on the distribution of bootstrapped samples. We found that estimated ICERs to be > $500,000 per QALY for all stakeholder perspectives. For the abstinent-year effectiveness measure, we found XR-NTX before release to be cost-effective at a 95 % confidence level for willingness-to-pay values >$49,000 per abstinent-year, across all perspectives.

CONCLUSIONS

XR-NTX administered to persons who are incarcerated with OUD before release may provide value for stakeholders and bridge a well-known treatment gap for this vulnerable population. Lower than expected participant engagement and missing data limit our results, and study outcomes may be sensitive to methods that address missing data if replicated.

Mechanism of opioid addiction and its intervention therapy: Focusing on the reward circuitry and mu-opioid receptor

Opioid abuse and addiction have become a global pandemic, posing tremendous health and social burdens. The rewarding effects and the occurrence of withdrawal symptoms are the two mainstays of opioid addiction. Mu-opioid receptors (MORs), a member of opioid receptors, play important roles in opioid addiction, mediating both the rewarding effects of opioids and opioid withdrawal syndrome (OWS). The underlying mechanism of MOR-mediated opioid rewarding effects and withdrawal syndrome is of vital importance to understand the nature of opioid addiction and also provides theoretical basis for targeting MORs to treat drug addiction. In this review, we first briefly introduce the basic concepts of MORs, including their structure, distribution in the nervous system, endogenous ligands, and functional characteristics. We focused on the brain circuitry and molecular mechanism of MORs-mediated opioid reward and withdrawal. The neuroanatomical and functional elements of the neural circuitry of the reward system underlying opioid addiction were thoroughly discussed, and the roles of MOR within the reward circuitry were also elaborated. Furthermore, we interrogated the roles of MORs in OWS, along with the structural basis and molecular adaptions of MORs-mediated withdrawal syndrome. Finally, current treatment strategies for opioid addiction targeting MORs were also presented.

Population-level impact of initiating pharmacotherapy and linking to care people with opioid use disorder at inpatient medically managed withdrawal programs: an effectiveness and cost-effectiveness analysis

BACKGROUND AND AIMS

Medications for opioid use disorder (MOUD) are shown to reduce opioid use and the risk of overdose. People with opioid use disorder (OUD) who exit inpatient medically managed withdrawal programs (detox) without initiating MOUD and linking to outpatient care have high rates of overdose. While detox encounters provide a theoretical opportunity for MOUD initiation, this is not ubiquitous in the United States. We used simulation modeling to estimate the population-level health effects and cost-effectiveness of a policy encouraging MOUD initiation during inpatient detox encounters.

DESIGN, SETTING AND PARTICIPANTS

We employed a dynamic population state-transition model to evaluate the effectiveness and cost-effectiveness of using detox programs as venues for initiating MOUD in Massachusetts, United States. We compared standard of care, where no detox patients initiate MOUD or link to outpatient MOUD providers, to strategies of offering MOUD to detox patients and linking those patients to outpatient MOUD.

MEASURES

Budgetary impact to the Massachusetts health-care sector, incremental cost-effectiveness ratios (ICER) and total counts and percentage differences of fatal overdoses prevented.

FINDINGS

Initiating MOUD in detox with perfect linkage to outpatient MOUD would reduce fatal overdoses by 4.5% [95% confidence interval (CI) = 2.3-5.9], at an ICER of $56 000 per quality-adjusted life-year (QALY) gained, compared with the standard of care. With moderate linkage, fatal overdoses would be reduced by 2.3% (95% CI= 1.2-3.1) with an ICER of $78 500 per QALY gained, compared with standard of care. Budgetary increase to Massachusetts health-care spending ranged from 0.5-1%.

CONCLUSION

A simulation model indicates that initiation of medications for opioid use disorder and linkage policies among detox patients in Massachusetts, USA could prevent fatal opioid overdoses in the opioid use disorder population and would be cost-effective from a health-care sector perspective.

The association between medication for opioid use disorder and employment outcomes in the U.S.: The relevance of race and ethnicity

•White admissions given MOUD were less likely to become unemployed at discharge.•Blacks and Hispanics given MOUD were more likely to remain unemployed at discharge.•Racial disparities associated with MOUD have notable implications for policy.

Transcutaneous cervical vagus nerve stimulation reduces behavioral and physiological manifestations of withdrawal in patients with opioid use disorder: A double-blind, randomized, sham-controlled pilot study

BACKGROUND

Opioid Use Disorder (OUD) is a serious public health problem, and the behavioral and physiological effects of opioid withdrawal can be a major impediment to recovery. Medication for OUD is currently the mainstay of treatment; however, it has limitations and alternative approaches are needed.

OBJECTIVE

The purpose of this study was to assess the effects of transcutaneous cervical vagus nerve stimulation (tcVNS) on behavioral and physiological manifestations of acute opioid withdrawal.

METHODS

Patients with OUD undergoing acute opioid withdrawal were randomly assigned to receive double blind active tcVNS (N = 10) or sham stimulation (N = 11) while watching neutral and opioid cue videos. Subjective opioid withdrawal, opioid craving, and anxiety were measured using a Visual Analogue Scale (VAS). Distress was measured using the Subjective Units of Distress Scale (SUDS), and pain was measured using the Numerical Rating Scale (NRS) for pain. Electrocardiogram signals were measured to compute heart rate. The primary outcomes of this initial phase of the clinical trial (ClinicalTrials.gov NCT04556552) were heart rate and craving.

RESULTS

tcVNS compared to sham resulted in statistically significant reductions in subjective opioid withdrawal (p = .047), pain (p = .045), and distress (p = .004). In addition, tcVNS was associated with lower heart rate compared to sham (p = .026). Craving did not significantly differ between groups (p = .11).

CONCLUSIONS

tcVNS reduces behavioral and physiological manifestations of opioid withdrawal, and should be evaluated in future studies as a possible non-pharmacologic, easily implemented approach for adjunctive OUD treatment.

Sustained drug delivery strategies for treatment of common substance use disorders: Promises and challenges

Substance use disorders (SUDs) are a leading cause of death and other ill health effects in the United States and other countries in the world. Several approaches ranging from detoxification, behavioral therapy, and the use of antagonists or drugs with counter effects are currently being applied for its management. Amongst these, drug therapy is the mainstay for some drug abuse incidences, as is in place specifically for opioid abuse or alcohol dependence. The severity of the havocs observed with the SUDs has triggered constant interest in the discovery and development of novel medications as well as suitable or most appropriate methods for the delivery of these agents. The chronic need of such drugs in users warrants the need for their prolonged or sustained systemic availability. Further, the need to improve patient tolerance to medication, limit invasive drug use and overall treatment outcome are pertinent considerations for embracing sustained release designs for medications used in managing SUDs. This review aims to provide an overview on up-to-date advances made with regards to sustained delivery systems for the drugs for treatment of different types of SUDs such as opioid, alcohol, tobacco, cocaine, and cannabis use disorders. The clinical relevance, promises and the limitations of deployed sustained release approaches along with future opportunities are discussed.

The Potential of Methocinnamox as a Future Treatment for Opioid Use Disorder: A Narrative Review

The opioid epidemic is an ongoing public health crisis, and the United States health system is overwhelmed with increasing numbers of opioid-related overdoses. Methocinnamox (MCAM) is a novel mu opioid receptor antagonist with an extended duration of action. MCAM has potential to reduce the burden of the opioid epidemic by being used as an overdose rescue treatment and a long-term treatment for opioid use disorder (OUD). The currently available treatments for OUD include naloxone, naltrexone, and methadone. These treatments have certain limitations, which include short duration of action, patient non-compliance, and diversion. A narrative review was conducted using PubMed and Google Scholar databases covering the history of the opioid epidemic, pain receptors, current OUD treatments and the novel drug MCAM. MCAM could potentially be used as both a rescue and long-term treatment for opioid misuse. This is due to its pseudo-irreversible antagonism of the mu opioid receptor, abnormally long duration of action of nearly two weeks, and the possibility of using kappa or delta opioid receptor agonists for pain management during OUD treatment. MCAM’s novel pharmacokinetic and pharmacodynamic properties open a new avenue for treating opioid misuse.

Relative effectiveness of medications for opioid-related disorders: A systematic review and network meta-analysis of randomized controlled trials

INTRODUCTION

Several pharmacotherapeutic interventions are available for maintenance treatment for opioid-related disorders. However, previous meta-analyses have been limited to pairwise comparisons of these interventions, and their efficacy relative to all others remains unclear. Our objective was to unify findings from different healthcare practices and generate evidence to strengthen clinical treatment protocols for the most widely prescribed medications for opioid-use disorders.

METHODS

We searched Medline, EMBASE, PsycINFO, CENTRAL, and ClinicalTrials.gov for all relevant randomized controlled trials (RCT) from database inception to February 12, 2022. Primary outcome was treatment retention, and secondary outcome was opioid use measured by urinalysis. We calculated risk ratios (RR) and 95% credible interval (CrI) using Bayesian network meta-analysis (NMA) for available evidence. We assessed the credibility of the NMA using the Confidence in Network Meta-Analysis tool.

RESULTS

Seventy-nine RCTs met the inclusion criteria. Due to heterogeneity in measuring opioid use and reporting format between studies, we conducted NMA only for treatment retention. Methadone was the highest ranked intervention (Surface Under the Cumulative Ranking [SUCRA] = 0.901) in the network with control being the lowest (SUCRA = 0.000). Methadone was superior to buprenorphine for treatment retention (RR = 1.22; 95% CrI = 1.06-1.40) and buprenorphine superior to naltrexone (RR = 1.39; 95% CrI = 1.10-1.80). However, due to a limited number of high-quality trials, confidence in the network estimates of other treatment pairs involving naltrexone and slow-release oral morphine (SROM) remains low.

CONCLUSION

All treatments had higher retention than the non-pharmacotherapeutic control group. However, additional high-quality RCTs are needed to estimate more accurately the extent of efficacy of naltrexone and SROM relative to other medications. For pharmacotherapies with established efficacy profiles, assessment of their long-term comparative effectiveness may be warranted.

TRIAL REGISTRATION

This systematic review has been registered with PROSPERO (https://www.crd.york.ac.uk/prospero) (identifier CRD42021256212).