Extended-release naltrexone (XR-NTX) for opioid use disorder in clinical practice: Vivitrol's Cost and Treatment Outcomes Registry

Attitudes toward extended-release naltrexone treatment for opioid use disorder among African Americans

BACKGROUND

Extended-release naltrexone (XR-NTX; Vivitrol®) is a long-acting injectable form of naltrexone, which is a medication used to treat opioid use disorder (OUD). In 2010, XR-NTX received Food and Drug Administration approval to treat OUD, becoming the first non-addictive and non-psychoactive medication for this condition. Because uptake of XR-NTX has been relatively low, less is known regarding how persons with OUD view this form of treatment. And because previous studies tend to rely on samples that lack racial diversity or are conducted outside the United States, we know very little about how African Americans view XR-NTX. The objective of this study, therefore, was to identify/explain the most salient attitudes toward XR-NTX as a form of OUD treatment among African Americans.

METHODS

In-depth interviews (n = 30) were conducted with a sample of African American adults who used opioids in Southwest Florida between August 2021 and February 2022. Audiotapes of interviews were transcribed, coded, and thematically analyzed.

RESULTS

Analyses revealed that participants' attitudes toward XR-NTX were generally positive. Specifically, participants found XR-NTX's monthly injection administration, non-addictive and non-intoxicating properties, and perceived effectiveness (compared to other medications for OUD) most appealing.

CONCLUSIONS

Study findings suggest that African Americans who use opioids may have more favorable attitudes toward XR-NTX than other medications for OUD (e.g., methadone), which tend to be highly stigmatized. These data uniquely contribute to the literature by capturing the voices of African Americans who use opioids, a group with high rates of opioid-related deaths.

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.

Continued Posttrial Benefits of Buprenorphine Extended Release: RECOVER Study Findings

BACKGROUND

This analysis describes participants' opioid use disorder (OUD) outcomes for 18 months after discontinuing extended-release buprenorphine injection (BUP-XR, SUBLOCADE).

METHODS

The RECOVER (Remission From Chronic Opioid Use: Studying Environmental and Socioeconomic Factors on Recovery) study recruited participants from BUP-XR clinical trials (NCT02357901, NCT025100142, and NCT02896296) to assess whether there were sustained benefits after leaving the trial. Abstinence from opioids and from all illicit substances (excluding medical cannabis), health-related quality of life, depression, and employment were measured after BUP-XR discontinuation and change in outcomes assessed at 6, 12, and 18 months. Results were analyzed within the full cohort and by duration of BUP-XR treatment (0-2 months, 3-5 months, 6-11 months, 12 months, or 13-18 months) with and without inverse probability weights adjusting for differences in baseline characteristics.

RESULTS

Of 533 participants, 529 were assessed over the 18-month study period. Further posttrial pharmacotherapy was reported by 33% of participants. At RECOVER baseline, longer BUP-XR was associated with higher abstinence (0-2 months BUP-XR [n = 116]: 38.8%; 3-5 months BUP-XR [n = 61]: 41.0%; 6-11 months BUP-XR [n = 86]: 68.6%; 12 months BUP-XR [n = 135]: 71.9%; 18 months BUP-XR [n = 131]: 88.2%) and greater 12-Item Short Form Health Survey mental component scores. Over 60% of participants had stable or improved outcomes at 6, 12, and 18 months assessments. Overall 47% of participants self-reported sustained opioid abstinence for the full 18-month follow-up, with greater sustained abstinence associated with longer BUP-XR treatment duration. A sensitivity analysis, removing patients receiving medications for OUD, yielded similar results.

CONCLUSIONS

Participants from BUP-XR clinical trials who continued into RECOVER maintained or improved on numerous outcomes over 18 months, demonstrating the long-term positive impact of OUD pharmacotherapy.

Attitudes toward opioid use disorder pharmacotherapy among recovery community center attendees

BACKGROUND

Despite their proven efficacy, medications for opioid use disorder (MOUD) are underutilized. Negative beliefs and attitudes toward MOUD are quite common, yet rapidly expanding recovery community centers (RCCs) may offer a promising venue for fostering MOUD support as they operate under the maxim, "many pathways [to recovery], all should be celebrated" and are utilized mainly by those with opioid use disorder. The current study provides a first look at MOUD attitudes and their correlates in RCC attendees.

METHODS

The study conducted a cross-sectional survey (N = 320) of recovering adults attending 31 RCCs across New England, assessing demographic, treatment, and recovery-relevant factors, as well attitudes (positive vs. negative) toward the use of agonist and antagonist MOUD. The study used frequencies and confidence intervals to obtain prevalence estimates for positive and negative attitudes toward agonist and antagonist MOUD, and to examine differences between them. Spearman correlations identified correlates of MOUD attitudes (at p < 0.10), and significant correlates were assessed for unique contributions via multivariable logistic regression.

RESULTS

Positive attitudes were common and more prevalent than negative attitudes for both agonist (positive: 71.4 [66.1, 76.3]%; negative: 28.6 [23.7, 33.9]%) and antagonist (positive: 76.5 [71.4, 81.1]%; negative: 23.5 [18.9, 28.6]%) MOUD, which did not differ. The study identified several correlates of MOUD attitudes at the p < 0.10 level, but only four variables emerged as unique predictors controlling for other correlates. Lifetime history of agonist MOUD treatment was uniquely associated with positive agonist attitudes (p = 0.008), whereas greater social support for recovery was associated with positive antagonist attitudes (p = 0.007). Lower educational attainment was uniquely associated with negative antagonist attitudes (p = 0.005), and a greater degree of spirituality was related to negative attitudes toward both agonists (p = 0.005) and antagonists (p = 0.01).

CONCLUSIONS

Findings reveal very high rates of positive MOUD attitudes among RCC participants, highlighting the potential for this growing tier of recovery support to foster acceptance and peer support for medication-facilitated recovery pathways. Correlates of attitudes further reveal opportunities for facilitating MOUD acceptance within and beyond the RCC network.

Pilot testing a tool to determine the costs and time associated with community pharmacy-based administration of injectable naltrexone

BACKGROUND

Medications for opioid use disorder (MOUD), including injectable naltrexone (IN), are part of evidence-based OUD treatments. MOUD access often is limited, especially in rural communities. When authorized to administer non-vaccination injections, pharmacists can increase IN accessibility. However, inadequate reimbursement for pharmacist-administered IN can hinder widespread adoption.

OBJECTIVES

To pilot test a process to obtain a preliminary estimate of the total costs and time associated with community-pharmacist administered IN.

METHODS

A purposively-selected sample of key informants at community pharmacies administering IN were surveyed about time and cost for best practice IN activities. Respondents estimated the time to perform activities and average pharmacist/pharmacy technician hourly salary, which were used to calculate administration costs.

RESULTS

The approach to estimate time and costs was feasible. Administrative costs (mean = $93, range: $48-$164) and time (mean = 123 min., range: 63-220 min.) to administer IN varied widely. Pharmacists'/pharmacy technicians' roles varied by pharmacy.

CONCLUSIONS

Pharmacists allocate significant time and resources to administer IN. Insufficient reimbursement may disincentivize pharmacy-involved OUD treatment and ultimately slow needed expansion of MOUD services. Increasing IN services requires engaging pharmacies to expand their practice through educational campaigns, along with a commitment to reimburse the cost of medications and related administration activities.

Evaluation of Opioid Overdose Reports in Patients Treated with Extended-Release Naltrexone: Postmarketing Data from 2006 to 2018

INTRODUCTION

After treatment with naltrexone extended-release injectable suspension (XR-NTX), a µ-opioid receptor antagonist, opioid tolerance is reduced from pretreatment baseline. Patients may be vulnerable to opioid overdose if they attempt to override the blockade during treatment, at the end of a dosing interval, after missing a dose, or after discontinuing treatment.

OBJECTIVE

We analyzed postmarketing data to characterize reporting rates of opioid overdose during treatment with and after discontinuation of XR-NTX.

METHODS

Postmarketing adverse event reports within the XR-NTX safety database, received 2006-2018, for patients treated with XR-NTX for any indication were reviewed for opioid overdose cases. Assessable cases were categorized by timing of the event from the last dose of XR-NTX (latency): ≤28 days (on treatment), 29-56 days, and >56 days from last dose of XR-NTX. Within each latency group, cases were further classified as serious and, of those, cases that had a fatal outcome.

RESULTS

During the 12-year period, an estimated 495,602 patients received XR-NTX. Opioid overdose was reported in 161 cases; of these, 66 contained sufficient information to determine latency. Reporting rates of opioid overdose per 10,000 patients treated were similar among latency groups: 0.54 for ≤28 days (0.24 fatal), 0.34 for 29-56 days (0.16 fatal), and 0.44 for >56 days (0.40 fatal) from the last dose of XR-NTX.

CONCLUSIONS

Over the 12-year period, the reporting rates of opioid overdose were similar during treatment with or after discontinuation of XR-NTX and <10/10,000 patients exposed. Our findings are limited by the nature of spontaneously reported safety data.

Negative affect-associated drug refusal self-efficacy, illicit opioid use, and medication use following short-term inpatient opioid withdrawal management

INTRODUCTION

Persons with opioid use disorder (OUD) are prone to frequent relapse following brief inpatient medically managed withdrawal. This longitudinal, naturalistic study examines associations among illicit opioid use, use of medication for opioid use disorder (MOUD), and one's confidence in the ability to resist drug use in the face of negative emotions (i.e., negative affect-associated drug refusal self-efficacy).

METHOD

Participants were 220 adults with OUD who recently completed a short-term inpatient program and the study followed for 6 months. At baseline, participants reported demographics, illicit opioid use, recent engagement with MOUD, and negative affect-associated drug refusal self-efficacy. At follow-up (1 week and 1-, 3-, and 6-months following discharge), participants reported illicit opioid use and MOUD.

RESULTS

Participants averaged 30.7 years of age, 63.2% were male, and 84.1% were white. Both illicit opioid use and rates of MOUD increased during the 6-month follow-up period, although only 34.1% received MOUD. At baseline, participants reported less than 50% self-confidence to resist using opioids during negative emotional states. Baseline negative affect-associated drug refusal self-efficacy inversely predicted illicit opioid use (p = .01) at follow-up but was not associated with follow-up MOUD.

CONCLUSION

Among persons with OUD, lower confidence to resist using opioids in negative emotional states predicts greater use of illicit opioids in the months following medically managed withdrawal, even with receipt of MOUD.

Community pharmacy-based injectable naltrexone service delivery models and best practices

BACKGROUND

Opioid use disorder (OUD) is a major public health issue in the United States. Medications for OUD (MOUD), which combines the use of approved medications with counseling and behavioral therapies, represents an evidence-based approach to treat individuals living with an OUD. However, MOUD has not kept up with increased demand and new treatment approaches are needed. One approach is injectable naltrexone, an approved and effective MOUD treatment, provided by pharmacists, who are more geographically accessible and have legal authority to administer it in some states.

OBJECTIVES

To explore how different community pharmacists provide injectable naltrexone treatment and identify best practices.

METHODS

An exploratory sequential mixed-methods design was used to investigate pharmacy-based naltrexone injection practices, involving a pharmacist questionnaire and interviews with pharmacists, prescribers, and community stakeholders. An inductive/iterative content analysis approach, guided by an initial straw model, was used to identify and explore conceptual categories for the interviews.

RESULTS

The final sample included 68 pharmacy surveys and 14 total interviews with pharmacists (n = 9), prescribers (n = 3), and community stakeholders (n = 2). Pharmacies providing naltrexone injections reported administering over 700 injections in the past year. Interviews revealed benefits and barriers to pharmacist-provided injections and the importance of the prescriber-pharmacist relationship in OUD treatment. Three pharmacy treatment delivery models were identified, compared to the initial straw model, and informed development of a best practices checklist for community pharmacies interested in establishing or expanding a naltrexone injection service.

CONCLUSIONS

The study demonstrates how community pharmacies developed and implemented a naltrexone injection service. Pharmacists' and prescribers' feedback clearly suggests an untapped interest, as well as resources, in realizing pharmacists' roles as providers of injectable naltrexone treatment. Implementation research could inform the development and evaluation of an intervention based on these best practices to further explore the utility of community pharmacy-based naltrexone injection services.

Endogenous Opiates and Behavior: 2018

This paper is the forty-first consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2018 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (2), the roles of these opioid peptides and receptors in pain and analgesia in animals (3) and humans (4), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (5), opioid peptide and receptor involvement in tolerance and dependence (6), stress and social status (7), learning and memory (8), eating and drinking (9), drug abuse and alcohol (10), sexual activity and hormones, pregnancy, development and endocrinology (11), mental illness and mood (12), seizures and neurologic disorders (13), electrical-related activity and neurophysiology (14), general activity and locomotion (15), gastrointestinal, renal and hepatic functions (16), cardiovascular responses (17), respiration and thermoregulation (18), and immunological responses (19).

A mixed-method comparison of physician-reported beliefs about and barriers to treatment with medications for opioid use disorder

BACKGROUND

Evidence demonstrates that medications for treating opioid use disorder (MOUD) -namely buprenorphine, methadone, and extended-release naltrexone-are effective at treating opioid use disorder (OUD) and reducing associated harms. However, MOUDs are heavily underutilized, largely due to the under-supply of providers trained and willing to prescribe the medications.

METHODS

To understand comparative beliefs about MOUD and barriers to MOUD, we conducted a mixed-methods study that involved focus group interviews and an online survey disseminated to a random group of licensed U.S. physicians, which oversampled physicians with a preexisting waiver to prescribe buprenorphine. Focus group results were analyzed using thematic analysis. Survey results were analyzed using descriptive and inferential statistical methods.

RESULTS

Study findings suggest that physicians have higher perceptions of efficacy for methadone and buprenorphine than for extended-release naltrexone, including for patients with co-occurring mental health disorders. Insurance obstacles, such as prior authorization requirements, were the most commonly cited barrier to prescribing buprenorphine and extended-release naltrexone. Regulatory barriers, such as the training required to obtain a federal waiver to prescribe buprenorphine, were not considered significant barriers by many physicians to prescribing buprenorphine and naltrexone in office-based settings. Nor did physicians perceive diversion to be a prominent barrier to prescribing buprenorphine. In focus groups, physicians identified financial, logistical, and workforce barriers-such as a lack of addiction treatment specialists-as additional barriers to prescribing medications to treat OUD.

CONCLUSIONS

Additional education is needed for physicians regarding the comparative efficacy of different OUD medications. Governmental policies should mandate full insurance coverage of and prohibit prior authorization requirements for OUD medications.

Impact of extended release naltrexone on health-related quality of life in individuals with legal involvement and opioid use disorders

BACKGROUND

Understanding the impact of medications for opioid use disorder on health related quality of life (QOL) may help to explain why few individuals with legal involvement remain in treatment, specifically those receiving opioid antagonists. QOL is an established predictor of treatment retention and has been shown to improve with some treatment for opioid use disorder. Yet limited research has examined QOL with opioid antagonists. We examined the impact of extended release naltrexone (XR-NTX) on QOL and retention in treatment in a randomized, multi-site trial of individuals with legal involvement. Methods: The participants were 308 community-dwelling adults with current or recent legal involvement with opioid dependence at five site across United States. They were randomized to receive XR-NTX or treatment as usual for 6 months. QOL was measured every 2 weeks using Euro QOL individual items, summary index score, and health state today metric. Results: No significant difference in QOL scores were observed between the two groups at the completion of active treatment or on follow up at 52 and 78 weeks. There were no time effects of treatment on scores. Contrary to expectation, baseline and average QOL did not predict retention in treatment. Conclusion: In contrast to prior research, our findings did not demonstrate significant changes (improvements or decreases) in QOL associated with XR-NTX treatment. Clinicians may consider that individuals receiving XR-NTX may not experience changes in perceived well-being in response to treatment and consider discussing with patients that they may not necessarily perceive improvement in their QOL. This may help to ground patient's expectations about the effects of treatment and potentially reduce attrition from treatment with opioid antagonists.

Medication-assisted therapies for opioid use disorders in patients with chronic pain

Opioids have been used to treat pain and invoke pleasure for centuries. Modern scientific advancements have led to more potent, synthetic opioids. While certainly more effective in treating pain, they can also be much more addictive. Over the years the scientific community has developed a clearer understanding of the role opioid receptors play in causing and treating opioid use disorders (OUD) and we now know that OUD can develop in individuals taking opioids for "legitimate" pain. Current guidelines suggest that all prescribers (especially those prescribing opioids) be capable treating OUD. Pharmacological advances have led to a wide array of safe and effective treatment options to address OUDs. This paper will discuss the history of opioid development, what is known about the transition from analgesic uses to addiction and modern evidenced based treatment strategies to address OUDs.

Opioid use and dropout from extended-release naltrexone in a controlled trial: implications for mechanism

BACKGROUND AND AIMS

Extended-release formulations of naltrexone have emerged as effective treatment options for opioid use disorder. This post-hoc analysis examined the temporal relationship between episodes of opioid use and subsequent dropout in a placebo-controlled trial of extended-release injection naltrexone (XR-NTX) to draw inferences about the mechanism by which extended blockade of opioid receptors translates into clinical effectiveness.

DESIGN

This was a 24-week multiple-site, double-blind, randomized trial of monthly XR-NTX versus placebo injections. We analyzed time to dropout from treatment using survival analysis with an extended Cox model as a function of treatment (XR-NTX versus placebo) and with weekly urine drug test (UDT) results for opioids at each week as a time-dependent covariate.

SETTING

Thirteen addiction treatment programs in Russia, 2008-09.

PARTICIPANTS

A total of 250 adults with opioid use disorder who had completed in-patient detoxification.

INTERVENTION

XR-NTX injection or placebo injection every 4 weeks with weekly clinic visits and biweekly counseling.

MEASUREMENTS

Urine toxicology for opioids measured weekly and week of dropout from treatment.

FINDINGS

The Cox model yielded a significant interaction of time-dependent urine toxicology by treatment (P = 0.024). Among patients receiving placebo, a positive UDT in a given week increased the risk for dropout from treatment in the subsequent week [hazard ratio (HR) = 6.25; 95% confidence interval (CI) = 3.6-10.0], whereas among patients receiving XR-NTX, a positive UDT result showed no significant effect on risk for dropout (HR = 1.67; 95% CI = 0.6-4.5). The proportion of patients who completed all 24 weeks without any positive UDT result was 31% on XR-NTX compared with 20% on placebo (P = 0.051).

CONCLUSIONS

Extended-release injection naltrexone was effective at reducing the risk of dropout from opioid use disorder treatment after an episode of opioid use. Just under a third of patients (31%) on XR-NTX had no opioid-positive urine tests across the trial, but the hypothesis that this would differ from placebo (20%) was not confirmed.

Nanomedicines - Tiny particles and big challenges

After decades of research, nanotechnology has been used in a broad array of biomedical products including medical devices, drug products, drug substances, and pharmaceutical-grade excipients. But like many great achievements in science, there is a fine balance between the risks and opportunities of this new technology. Some materials and surface structures in the nanosize range can exert unexpected toxicities and merit a more detailed safety assessment. Regulatory agencies such as the United States Food and Drug Administration or the European Medicines Agency have started dealing with the potential risks posed by nanomaterials. Considering that a thorough characterization is one of the key aspects of controlling such risks this review presents the regulatory background of nanosafety assessment and provides some practical advice on how to characterize nanomaterials and drug formulations. Further, the challenges of how to maintain and monitor pharmaceutical quality through a highly complex production processes will be discussed.

Medication-Assisted Treatment for Opioid-Use Disorder

The United States is in the midst of a national opioid epidemic. Physicians are encouraged both to prevent and treat opioid-use disorders (OUDs). Although there are 3 Food and Drug Administration-approved medications to treat OUD (methadone, buprenorphine, and naltrexone) and there is ample evidence of their efficacy, they are not used as often as they should. We provide a brief review of the 3 primary medications used in the treatment of OUD. Using data from available medical literature, we synthesize existing knowledge and provide a framework for how to determine the optimal approach for outpatient management of OUD with medication-assisted treatments.

Potential uses of naltrexone in emergency department patients with opioid use disorder

Introduction: Despite widespread recognition of the opioid crisis, opioid overdose remains a common reason for Emergency Department (ED) utilization. Treatment for these patients after stabilization often involves the provision of information for outpatient treatment options. Ideally, an ED visit for overdose would present an opportunity to start treatment for opioid use disorder (OUD) immediately. Although widely recognized as effective, opioid agonist therapy with methadone and buprenorphine commonly referred to as "medication-assisted therapy" but more correctly as "medication for addiction treatment" (MAT), can be difficult to access even for motivated individuals due to shortages of prescribers and treatment programs. Moreover, opioid agonist therapy may not be appropriate for all patients, as many patients who present after overdose are not opioid dependent. More treatment options are required to successfully match patients with diverse needs to an optimal treatment plan in order to avoid relapse. Naltrexone, a long-acting opioid antagonist, available orally and as a monthly extended-release intramuscular injection, may represent another treatment option. Methods: We conducted a literature search of MEDLINE and PubMed. We aimed to capture references related to naltrexone and is use as MAT for OUD, as well as manuscripts that discussed naltrexone in comparison toother agents used for MAT, opioid detoxification, and naltrexone metabolism. Our initial search logic returned a total of 618 articles. Following individual evaluation for relevance, we selected 65 for in-depthreview. Manuscripts meeting criteria were examined for citations meriting further review, leading to the addition of 30 manuscripts Conclusions: Here, we review the pharmacology of naltrexone as it relates to OUD, its history of use, and highlight recent studies and new approaches for use of the drug as MAT including its potential initiation after ED visit for opioid overdose.

Systematic Analysis of the Service Process and the Legislative and Regulatory Environment for a Pharmacist-Provided Naltrexone Injection Service in Wisconsin

Community pharmacists are viewed by the public as convenient and trustworthy sources of healthcare and pharmacists likely can play a larger role in addressing the major public health issue of the opioid epidemic affecting Wisconsin residents. Approved medications, including long-acting injectable naltrexone, can transform the treatment of individuals with opioid use disorder (OUD). Due to shortages of behavioral health providers in the U.S., and pharmacists' knowledge about the safe use of medications, pharmacists can be a significant access point for treating OUD with naltrexone. Wisconsin's pharmacy practice laws authorize pharmacists to administer medications via injection, and a small number of pharmacists currently are using this authority to provide a naltrexone injection service. This exploratory study had two objectives: (1) describe the pharmacist injection service process and identify barriers and facilitators to that service and (2) analyze the legislative/regulatory environment to ascertain support for expanding naltrexone injection service. Semi-structured pharmacist interviews (n = 4), and an analysis of Wisconsin statutes/regulations governing public health and social services, were undertaken to explore the objectives. Findings suggest that the service process requires considerable coordination and communication with practitioners, patients, and pharmacy staff, but many opportunities exist to broaden and sustain the service throughout Wisconsin.