The Pharmacology of Buprenorphine Microinduction for Opioid Use Disorder

Retrospective Observational Descriptive Study on Use and Rotations to Belbuca®

The purpose of this study was to better characterize morphine equivalent daily dose (MEDD) equivalencies with buccal buprenorphine, and identify real-world efficacy and safety outcomes associated with the use of buccal buprenorphine for chronic pain at a local VA Medical Center. This study was a retrospective chart review of Computerized Patient Record System (CPRS) patient records with outpatient prescriptions for buccal buprenorphine (Belbuca®). Overall, there was a high discontinuation rate of Belbuca®: being 60% or greater across all different patient groups. These high attrition rates may potentially be result of failure to titrate to an optimal dose of Belbuca® needed for adequate analgesia. Those fully rotated fared marginally better than those partially rotated in that those fully rotated discontinued at a lesser rate and less quickly than those who were partially rotated. From the results of this study, a local dosing scheme for Belbuca® based on baseline MEDD was created for facility level guidance. The exact MEDD conversion ratio, however, for individual buprenorphine products as well as MEDD contributed by these products on a patient's overall opioid related risk compared to other full agonist opioids still remains unclear and further studies are warranted.

Outpatient Initiation of 7-Day Injectable Buprenorphine: A Direct-to-Inject Case Series

BACKGROUND

Buprenorphine is an effective treatment for opioid use disorder, but it can be challenging to avoid withdrawal in the process of buprenorphine initiation. After the recent FDA approval of 7-day long-acting injectable buprenorphine, some clinicians have used this formulation to start patients on buprenorphine without a prior sublingual "test dose." Very little is known about the feasibility of this practice in an outpatient setting.

CASES

In this case series, we conducted a retrospective chart review of electronic health record data for all patients who were ordered 7-day long-acting injectable buprenorphine for a "direct-to-inject" initiation within a single public health system from January 1, 2024 to November 15, 2024. We excluded patients who received a cumulative dose of 4 mg or more of sublingual buprenorphine in the 24 hours before injection. We reported on chart-documented patient experiences after injection, whether patients returned to care, and retention on buprenorphine at 7- and 30-days post-injection. We identified 21 unique patients who received direct-to-inject buprenorphine in 22 attempts. In 17 (77%) attempts, the patient received no buprenorphine in the preceding 24 hours. In 5 (23%) attempts, patients received some buprenorphine in the preceding 24 hours (<4 mg) and/or had evidence of buprenorphine in a same-day urine drug screen. Patient experiences post-injection fit into 1 of 3 themes: "It felt fine" (n = 6), "I felt unwell but okay" (n = 13), and "It felt very rough" (n = 3). Most attempts resulted in buprenorphine treatment retention at 7 days (n = 17, 77%) and 30 days (n = 16, 73%) after injection.

DISCUSSION

Direct-to-inject buprenorphine was generally well tolerated, with excellent retention on buprenorphine at 7- and 30 days post-injection. Further research is needed to evaluate the correlation between preinjection patient characteristics (time since last use, level of withdrawal) and post-injection patient experience of withdrawal.

Barriers to Buprenorphine Treatment Among People Experiencing Homelessness: A Qualitative Study from the Provider Perspective

People experiencing homelessness (PEH) face a high risk of opioid-related deaths, yet there is limited qualitative data on the barriers encountered when accessing buprenorphine treatment for opioid use disorder (OUD). To address this gap, we interviewed 28 clinicians, outreach workers, and administrators from organizations serving PEH with OUD. Our goal was to understand the barriers and facilitators at the patient, clinic, and institutional levels and gather recommendations for improvement. Interviews, conducted via Zoom and analyzed through thematic analysis, revealed several barriers. At the patient level, themes related to barriers included knowledge and experience (e.g., limited knowledge about buprenorphine options; rejection of buprenorphine due to prior experience with precipitated withdrawal); concerns about the medication and its administration (e.g., distrust of injectable medications; concerns about treatment control, and a prolonged informed consent process for extended-release injectable buprenorphine); and challenges due to homelessness (e.g., identification requirement to access medication at pharmacies, difficulties managing buprenorphine while unsheltered). At the clinic level, themes centered around staffing (e.g., lack of training and experience in treating PEH and staffing shortages) and health care-related stigma (e.g., discriminatory attitudes toward PEH with OUD). Institutional-level themes included state-regulatory factors (e.g., practice regulations limiting clinical pharmacists' ability to prescribe buprenorphine) and access factors (e.g., stigmatization of buprenorphine prescribing, limited low-barrier buprenorphine access, and care system complexity). Recommendations included educational programs for patients and clinicians to increase understanding and reduce stigma, integrating buprenorphine treatment into non-traditional settings, and providing housing with treatment.

Lessons from the National institutes of health innovation corps program: defining barriers to developing and commercializing novel solutions for persons with opioid use disorder

BACKGROUND

Translating innovative research advancements into commercially viable medical interventions presents well-known challenges. However, there is limited understanding of how specific patient, clinical, social, and legal complexities have further complicated and delayed the development of new and effective interventions for Opioid Use Disorder (OUD). We present the following case studies to provide introductory clinical, social, and business insights for researchers, medical professionals, and entrepreneurs who are considering or are currently developing medical.

METHODS

Four small business recipients of National Institute on Drug Abuse (NIDA) small business grant funding collected a total of 416 customer discovery interviews during the 2021 National Institutes of Health (NIH) Innovation-Corps (I-Corps) program. Each business received funding to advance an OUD-specific innovation: therapeutics (2 companies), medical device (1 company), and Software as a Medical Device (SaMD) (1 company). Interview participants included stakeholders from a variety of disciplines of Substance Use Disorders (SUD) healthcare including clinicians, first responders, policymakers, relevant manufacturers, business partners, advocacy groups, regulatory agencies, and insurance companies.

RESULTS

Agnostic to the type of product (therapeutic, device, or SaMD), several shared barriers were identified: (1) There is a lack of standardization across medical providers for managing patients with OUD, resulting in diverse implementation practices due to a fragmented healthcare policy; (2) Underlying Social Determinants of Health (SDOH) present unique challenges to medical care and contribute to poor outcomes in OUD; (3) Stigma thwarts adoption, implementation, and the development of innovative solutions; (4) Constantly evolving public health trends and legal policies impact development and access to OUD interventions.

CONCLUSION

It is critical for innovators to have early interactions with the full range of OUD stakeholders to identify and quantify true unmet needs and to properly position development programs for commercial success. The NIH I-Corps program provides a framework to educate researchers to support their product design and development plans to increase the probability of a commercially successful outcome to address the ongoing opioid epidemic.

Initiating buprenorphine to treat opioid use disorder without prerequisite withdrawal: an updated systematic review

BACKGROUND

Withdrawal prior to buprenorphine initiation may be intolerable or create barriers to therapy. We aim to update our previous systematic review on the efficacy and safety of buprenorphine initiation strategies that aim to omit prerequisite opioid withdrawal (POW).

METHODS

We used the same search strategy for this update as in the original review with the modification of an additional term "low dose." We searched Embase and Scopus from April 11, 2020 to August 1, 2024 with searches in Google Scholar and www.

CLINICALTRIALS

gov . A study was included if it described patients with opioid use disorder or chronic pain that transitioned from a full mu-opioid agonist to buprenorphine without preceding withdrawal and reported withdrawal during initiation as an outcome. Two investigators independently screened citations and articles for inclusion, collected data using a standardized data collection tool, and assessed study risk of bias.

RESULTS

Forty-four articles met our inclusion criteria; 31 were case reports/series reporting 84 cases and 13 were single-arm observational studies reporting a total of 576 cases. These studies were added to the literature from our original systematic review, totaling 59 studies and 682 patients. Sublingual buprenorphine was the most common initial formulation, comprising 55% (376/682) of cases. In case reports/series, use of a validated scale to measure withdrawal was uncommon; validated scales were only used in 36% of patients. All other patients had withdrawal assessed in a manner not utilizing a validated scale. Approximately half of these patients experienced any level of withdrawal (57/106 = 54%). The specific outcome of "any level of withdrawal" was not consistently reported in single-arm observational studies. Eight studies reported on any level of withdrawal, which occurred in 41% (177/428) of initiation attempts; some patients experienced more than one initiation attempt. Thirteen patients in case reports/series and 37 patients in the single-arm observational studies reported clinically significant withdrawal (50/682 = 7%). 81% (451/555) of patients transitioned to buprenorphine.

CONCLUSION

The prevalence of buprenorphine dosing strategies that aim to omit POW has vastly increased over the past 4 years. While quality of evidence remains low, the increased quantity of publications and integration into health-system guidelines and protocols demonstrates the need for prospective, controlled studies. It is unknown how selection bias impacts current findings, further highlighting the need for prospective, randomized, controlled trials evaluating these dosing strategies.

Buprenorphine Pharmacodynamics: A Bridge to Understanding Buprenorphine Clinical Benefits

Buprenorphine is an agonist at the mu opioid receptor (MOR) and antagonist at the kappa (KOR) and delta (DOR) receptors and a nociceptin receptor (NOR) ligand. Buprenorphine has a relatively low intrinsic efficacy for G-proteins and a long brain and MOR dwell time. Buprenorphine ceiling on respiratory depression has theoretically been related multiple factors such as low intrinsic efficacy at MOR, binding to six-transmembrane MOR and interactions in MOR/NOR heterodimers. Buprenorphine reduces analgesic tolerance by acting as a delta opioid receptor (DOR) antagonist. As a kappa opioid receptor (KOR) antagonist, buprenorphine reduces craving associated with addiction. Buprenorphine is a model opioid for the ordinal bifunctional analogs BU10038, BU08028 which have been shown to be potent analgesics in non-human primates without reinforcing effects and little to no respiratory depression.

Challenges with current diagnosis and treatment strategies for precipitated opioid withdrawal in the emergency department and the role of the pharmacist

PURPOSE

To demonstrate the challenges with current diagnosis and treatment strategies for precipitated opioid withdrawal secondary to naloxone the emergency department (ED) setting and describe the role of the emergency medicine (EM) pharmacist in its management.

SUMMARY

There are no standardized criteria to define precipitated opioid withdrawal syndrome, so the diagnosis is typically based on sentinel signs and symptoms and time course. Complicating factors include a positive urine toxicology screen for nonopioid substances, comorbidities and associated medications prior to admission, medications given in the ED, and a fluctuating patient course during the ED stay that likely involves all these issues. Although buprenorphine is frequently recommended as the primary treatment for precipitated withdrawal, its use can be complicated if patients are on methadone maintenance or other long-acting opioids. The EM pharmacist plays a key role in managing patients with precipitated withdrawal.

CONCLUSION

Practice changes related to the diagnosis and treatment of opioid use disorder (OUD) with precipitated withdrawal in the ED are needed. EM pharmacists as part of the interprofessional care team have an important role in the management of patients with OUD, including those patients undergoing possible precipitated withdrawal.

Outpatient Low-Dose Initiation of Buprenorphine for People Using Fentanyl

Importance

The rise of high-potency opioids such as fentanyl makes buprenorphine initiation challenging due to the risks of precipitated withdrawal, prompting the exploration of strategies, such as low-dose initiation (LDI) of buprenorphine. However, no comparative studies on LDI outcomes exist.

Objective

To evaluate outpatient outcomes associated with 2 LDI protocols of buprenorphine among individuals with opioid use disorder (OUD) using fentanyl.

Design, Setting, and Participants

This cohort study analyzed data on adults with OUD who self-reported daily fentanyl use and underwent buprenorphine initiation using LDI. Data were extracted from the electronic health records of 2 substance use disorder treatment clinics using a specialty behavioral health pharmacy in San Francisco, California, from May 2021 to November 2022.

Exposures

Type of LDI protocol selected by individuals: 4-day or 7-day protocol.

Main Outcomes and Measures

The primary outcome was successful buprenorphine initiation, defined as self-reported LDI completion and pickup of a refill maintenance prescription, and buprenorphine retention. Logistic regression with generalized estimating equations assessed associations between LDI protocol (4-day vs 7-day) and successful initiation, adjusting for multiple attempts, age, gender identity, race and ethnicity, and housing status. Kaplan-Meier survival curves were used to estimate buprenorphine retention, and survival curves were adjusted using a fitted Cox proportional hazards regression model.

Results

A total of 126 individuals (median [IQR] age, 35 [29-44] years; 90 identified as men [71%]; 26 [21%] identified as Black or African American, 20 [16%] as Latine, and 66 [52%] as White individuals) with 175 initiation attempts were included. Across attempts, 72 (41%) had a 4-day LDI protocol and 103 (59%) had a 7-day protocol. Initiation was successful in 60 attempts (34%), including 27 (38%) among 4-day protocol and 29 (28%) among 7-day protocol attempts. Buprenorphine retention rate at 28 days was 21% for a 4-day protocol and 18% for a 7-day protocol. Logistic regression found no significant differences between LDI protocols and successful initiation, while repeated LDI attempts had lower odds of success (second attempt: adjusted odds ratio [AOR], 0.30 [95% CI, 0.14-0.66]; third or more attempt: AOR, 0.22 [95% CI, 0.09-0.53]). Unadjusted and adjusted survival models did not detect a significant difference in retention between LDI protocol types.

Conclusions and Relevance

This cohort study found that among people with OUD using fentanyl and attempting outpatient LDI of buprenorphine, successful buprenorphine initiation and retention rates were low. Future studies should examine interventions to improve LDI success and increase buprenorphine uptake and retention.

Incidence of buprenorphine-precipitated opioid withdrawal in adults with opioid use disorder: A systematic review

BACKGROUND AND AIMS

Buprenorphine is an evidence-based treatment for opioid use disorder, and the risk of precipitated withdrawal contributes to its underuse. The goal of this systematic review was to determine the incidence of buprenorphine-precipitated withdrawal in adults with opioid use disorder.

METHODS

This systematic review was registered on PROSPERO (CRD42023437634). We searched Medline, Embase Classic + Embase, and Cochrane CENTRAL from inception to 10 November 2023, and included original research that reported the incidence of sublingual buprenorphine-precipitated withdrawal in adults with opioid use disorder. Primary screening was completed by four independent reviewers. Full text review, data extraction and risk of bias assessments using the Newcastle Ottawa Scale and the Cochrane Risk of Bias 2 tool were completed by two independent reviewers. The primary outcome was precipitated withdrawal. Secondary outcomes were baseline opioids used, induction dose, initial Clinical Opiate Withdrawal Scale (COWS) score, location of induction, definition and severity of precipitated withdrawal and adverse events. The range of incidence of precipitated withdrawal across studies was described.

RESULTS

Our search yielded 10 197 unique citations. Twenty-one cohort and five randomized trials met inclusion criteria (n = 4497, range 20-1293). The overall incidence of precipitated withdrawal ranged from 0 to 13.2%. Nine studies defined precipitated withdrawal; definitions were inconsistent. Most patients used heroin at baseline. The most common initial dose of buprenorphine was between 2 mg and 8 mg (range: 0.075 mg-24 mg). Initial minimum COWS score ranged from 5 to 13. Induction locations included home, inpatient, emergency department, pre-hospital, outpatient and residential units. Of the fifteen studies with cases of precipitated withdrawal, nine studies did not report the severity of withdrawal experienced. Other induction-related adverse events varied. The overall quality of included studies was poor.

CONCLUSIONS

The best available evidence suggests the incidence of buprenorphine-precipitated withdrawal in adults with opioid use disorder is low and should not be a barrier to use.

Harm Reduction and Substance Use in Adolescents

This article discusses the use of substances among adolescents, the unacceptable overdose death rates they bear, and the relevant evidence-based harm reduction strategies available in primary care, including medications for opioid use disorder. Access to these medications, as well as to harm reduction strategies generally, is insufficient for adolescents. Many adolescents who use substances and who are most at risk for overdose regularly visit primary care, which is an appropriate setting for treatment and harm reduction delivery.

24-Hour Induction of Transdermal Buprenorphine to Buprenorphine Extended-Release

Buprenorphine is an effective treatment for opioid use disorder but can be slow when using a standard low-dose titration protocol to avoid precipitated withdrawal. This presents a substantial practical barrier in clinical practice. Recent low-dose induction strategies have attempted to simplify and shorten the process required for successful induction, including our own transdermal buprenorphine method, which achieves induction to sublingual buprenorphine/naloxone after 48 h. Here, we present two inpatients with active unregulated fentanyl use that were successfully initiated on buprenorphine extended-release with a novel 24-h transdermal buprenorphine protocol without precipitating withdrawal. This protocol may represent a substantial improvement in the practical feasibility of initiating buprenorphine for patients and providers, although further study is required to confirm efficacy and tolerability.

Rotation from methadone to buprenorphine using a micro-dosing regime in patients with opioid use disorder and serious mental illness: A case series

INTRODUCTION

Inducting buprenorphine from methadone has traditionally involved initial opioid withdrawal, with risk of mental state deterioration in patients with serious mental illness (SMI). Micro-dosing of buprenorphine, with small incremental doses, is a novel off-label approach to transitioning from methadone and does not require a period of methadone abstinence. Given the limited literature about buprenorphine microdosing, we aimed to evaluate the feasibility and safety of inducting buprenorphine in a series of patients on methadone with SMI.

METHODS

For this retrospective case series, we reviewed the records of 16 patients with SMI at a Melbourne addiction treatment centre, from January 2021 to July 2022, who transitioned via micro-dosing, from high-dose methadone (>30 mg) to buprenorphine and depot-buprenorphine. Psychiatric diagnoses, mental state, other substance withdrawal, transfer success, transition time, opioid withdrawal symptoms and overall patient experience were collected via objective and subjective reporting.

RESULTS

Methadone to buprenorphine transfer was completed by 88% of patients. Mental health measures remained stable with the exception of mildly increased anxiety. Median transfer time was 6.5 days for inpatients, 9 days for mixed setting and 10 days for outpatients. Most patients (93%) rated their experience 'manageable' reporting mild withdrawal symptoms. One patient met study criteria for precipitated withdrawal.

DISCUSSION AND CONCLUSIONS

This retrospective case series provides evidence that the use of a micro-dosing buprenorphine induction for methadone to buprenorphine transitions, including to depot-buprenorphine, has negligible risk, is tolerated by patients with SMI and is unlikely to precipitate an exacerbation of their mental illness.

Illicit Fentanyl Use and Hepatitis C Virus Seroconversion Among People Who Inject Drugs in Tijuana and San Diego: Results From a Binational Cohort Study

BACKGROUND

Illicitly manufactured fentanyl (IMF) increases overdose mortality, but its role in infectious disease transmission is unknown. We examined whether IMF use predicts hepatitis C virus (HCV) and human immunodeficiency virus (HIV) incidence among a cohort of people who inject drugs (PWID) in San Diego, California and Tijuana, Mexico.

METHODS

PWID were recruited during 2020-2022, undergoing semi-annual interviewer-administered surveys and HIV and HCV serological rapid tests through 2024. Cox regression was conducted to examine predictors of seroconversion considering self-reported IMF use as a 6-month lagged, time-dependent covariate.

RESULTS

Of 398 PWID at baseline, 67% resided in San Diego, 70% were male, median age was 43 years, 42% reported receptive needle sharing, and 25% reported using IMF. HCV incidence was 14.26 per 100 person-years (95% confidence interval [CI]: 11.49-17.02), and HIV incidence was 1.29 (95% CI: .49-2.10). IMF was associated with HCV seroconversion, with a univariable hazard ratio (HR) of 1.64 (95% CI: 1.09-2.40), and multivariable HR of 1.57 (95% CI: 1.03-2.40). The direction of the relationship with HIV was similar, albeit not significant (HR 2.39; 95% CI: .66-8.64).

CONCLUSIONS

We document a novel association between IMF and HCV seroconversion among PWID in Tijuana-San Diego. Few HIV seroconversions (n = 10) precluded our ability to assess if a similar relationship held for HIV. IMF's short half-life may destabilize PWID-increasing the need for repeat dosing and sharing smoking materials and syringes. New preventive care approaches may reduce HCV transmission in the fentanyl era.

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.

The Impact of High-Potency Synthetic Opioids on Pharmacotherapies for Opioid Use Disorder: A Scoping Review

BACKGROUND

The clinical implications of high potency synthetic opioids (HPSO) on medications for opioid use disorder (MOUDs) are not well understood. Although pharmacological interactions are plausible, the clinical significance of such interaction has not been systematically elucidated. This scoping review investigates the relationship between HPSO exposure and various MOUD treatment outcomes.

METHODS

We followed PRISMA-ScR (Preferred Reporting Items for Systematic reviews and Meta-Analyses Extension for Scoping Reviews) for scoping reviews with extensive a priori search strategy of databases: MEDLINE, EMBASE, PsycINFO, Web of Science, CINAHL, and Cochrane.

RESULTS

From 9149 studies, 34 fulfilled the inclusion criteria. Synthesized data reveal several critical insights: First, there is a variable but high occurrence (38%-80%) of HPSO usage among individuals with MOUDs. Second, MOUDs are linked to a decreased risk of overdoses and deaths associated with HPSO. Third, HPSO consumption is correlated with the risk of precipitated withdrawal when starting buprenorphine. Fourth, low-dose buprenorphine is being recognized as one method to avoid moderate withdrawal symptoms prior to treatment. Lastly, significant gaps exist in human experimental data concerning the effects of HPSO on key factors critical for treating OUD-craving, withdrawal symptoms, and pain.

CONCLUSIONS

Current evidence supports MOUD safety and effectiveness in reducing nonmedical opioid use. Further research is needed to explore HPSO's influence on the acute factors preceding nonmedical opioid use, such as cravings, withdrawal symptoms, and pain. This research could inform the optimization of MOUD dosing strategies. Achieving consensus and harmonizing data across clinical and research protocols could diminish variability, enhancing our understanding of HPSOs effect on MOUD treatment outcomes.

Initiation of Low-Dose Intravenous Buprenorphine for Opioid Use Disorder: A Case Series and Literature Review

Opioid use disorder (OUD) remains a significant public health challenge with patients often facing barriers to initiating medications for opioid use disorder (MOUD). Traditional initiation methods for buprenorphine-naloxone (buprenorphine/naloxone) can be challenging due to the longer duration of transition and the risk of precipitated withdrawal. This manuscript presents a case series of four patients who successfully transitioned to buprenorphine/naloxone maintenance using a novel approach: low-dose intravenous (IV) buprenorphine initiation. These cases presented in the manuscript involved patients with dual diagnoses of OUD and difficult-to-treat pain. Intravenous buprenorphine was administered at a dose of 0.3 mg every half-hour, with a maximum of four doses. Patients' withdrawal symptoms were monitored using the Clinical Opioid Withdrawal Scale (COWS). Comfort medications were provided as needed. All four patients were successfully transitioned to sublingual (SL) buprenorphine/naloxone without experiencing precipitated withdrawal. Patients were discharged with follow-up appointments at buprenorphine/naloxone clinics and bridge supplies of buprenorphine/naloxone. Low-dose IV buprenorphine initiation offers a rapid and effective method for transitioning patients from full-agonist opioids (FAOs) to buprenorphine/naloxone without precipitated withdrawal. This approach has the potential to increase treatment retention and patient satisfaction. This case series highlights the success of low-dose IV buprenorphine initiation in patients with OUD and chronic pain. Further research is needed to standardize this approach and assess long-term outcomes. Initiating MOUD with this method may improve patient care and reduce the burden on the healthcare system.

Rapid induction of transdermal buprenorphine to subcutaneous extended-release buprenorphine for the treatment of opioid use disorder

BACKGROUND

Buprenorphine is an effective and safe treatment for opioid use disorder, but the requirement for moderate opioid withdrawal symptoms to emerge prior to initiation is a significant treatment barrier.

CASE PRESENTATION

We report on two cases of hospitalized patients with severe, active opioid use disorder, in which we initiated treatment with transdermal buprenorphine over 48 h, followed by the administration of a single dose of sublingual buprenorphine/naloxone and then extended-release subcutaneous buprenorphine. The patients did not experience precipitated withdrawal and only had mild withdrawal symptoms.

CONCLUSIONS

This provides preliminary evidence for a rapid induction strategy that may improve tolerability, caregiver burden, and treatment retention as compared to previous induction strategies.

Novel Uses of Methadone Under the "72-Hour Rule" to Facilitate Transitions of Care and Low-Dose Buprenorphine Induction in an Outpatient Bridge Clinic

BACKGROUND

Federal regulations restrict methadone for opioid use disorder (OUD) treatment to licensed opioid treatment programs (OTPs). However, providers in other settings can administer methadone for opioid withdrawal under the "72-hour rule" while linking to further care. Prior work has demonstrated that methadone initiation in a low-barrier bridge clinic is associated with high OTP linkage and 1-month retention rates. We describe 2 other novel applications of the 72-hour rule in which methadone withdrawal management facilitated linkage to inpatient hospitalization and outpatient buprenorphine induction.

CASE PRESENTATIONS

Patient 1 was a 46-year-old woman with OUD complicated by serious injection-related infections. Severe opioid withdrawal limited her ability to tolerate emergency department wait times and receive inpatient care. We administered methadone for opioid withdrawal in an outpatient bridge clinic immediately before emergency department referral; this enabled hospital admission for intravenous antibiotics and anticoagulation. Patient 2 was a 36-year-old man with OUD desiring buprenorphine treatment. He had been unable to complete traditional buprenorphine induction without experiencing precipitated withdrawal. Thus, we recommended a low-dose buprenorphine induction overlapping with a full opioid agonist. Given the patient's preference to stop using fentanyl immediately, he received 72 hours of methadone for withdrawal treatment during the induction phase and successfully transitioned to buprenorphine without significant concomitant fentanyl use.

CONCLUSION

In addition to facilitating OTP linkage, on-demand 72-hour methadone administration for opioid withdrawal can reduce barriers to acute medical care and buprenorphine treatment.

Withdrawal during outpatient low dose buprenorphine initiation in people who use fentanyl: a retrospective cohort study

BACKGROUND

Buprenorphine is an effective treatment for opioid use disorder (OUD); however, buprenorphine initiation can be complicated by withdrawal symptoms including precipitated withdrawal. There has been increasing interest in using low dose initiation (LDI) strategies to reduce this withdrawal risk. As there are limited data on withdrawal symptoms during LDI, we characterize withdrawal symptoms in people with daily fentanyl use who underwent initiation using these strategies as outpatients.

METHODS

We conducted a retrospective chart review of patients with OUD using daily fentanyl who were prescribed 7-day or 4-day LDI at 2 substance use disorder treatment clinics in San Francisco. Two addiction medicine experts assessed extracted chart documentation for withdrawal severity and precipitated withdrawal, defined as acute worsening of withdrawal symptoms immediately after taking buprenorphine. A third expert adjudicated disagreements. Data were analyzed using descriptive statistics.

RESULTS

There were 175 initiations in 126 patients. The mean age was 37 (SD 10 years). 71% were men, 26% women, and 2% non-binary. 21% identified as Black, 16% Latine, and 52% white. 60% were unstably housed and 75% had Medicaid insurance. Substance co-use included 74% who used amphetamines, 29% cocaine, 22% benzodiazepines, and 19% alcohol. Follow up was available for 118 (67%) initiations. There was deviation from protocol instructions in 22% of these initiations with follow up. 31% had any withdrawal, including 21% with mild symptoms, 8% moderate and 2% severe. Precipitated withdrawal occurred in 10 cases, or 8% of initiations with follow up. Of these, 7 had deviation from protocol instructions; thus, there were 3 cases with follow up (3%) in which precipitated withdrawal occurred without protocol deviation.

CONCLUSIONS

Withdrawal was relatively common in our cohort but was mostly mild, and precipitated withdrawal was rare. Deviation from instructions, structural barriers, and varying fentanyl use characteristics may contribute to withdrawal. Clinicians should counsel patients who use fentanyl that mild withdrawal symptoms are likely during LDI, and there is still a low risk for precipitated withdrawal. Future studies should compare withdrawal across initiation types, seek ways to support patients in initiating buprenorphine, and qualitatively elicit patients' withdrawal experiences.

Buprenorphine Facilitates Rapid Weaning From Very-High-Dose Intrathecal Hydromorphone

Pain management in patients on chronic opioid therapy is a common clinical challenge. The phenomena of opioid-induced hyperalgesia and tolerance are important contributors to that challenge. There are multiple strategies described to wean opioid doses and/or transition patients off opioids altogether. However, there is very little data to guide transitions off chronic intrathecal opioids. Here, we report on two patients with intractable post-laminectomy pain syndrome, resulting in severe functional limitation in the setting of opioid escalation culminating in the intrathecal delivery of hydromorphone to daily doses as high as 20 mg/day. We describe their rapid successful weaning off opioids using low-dose buprenorphine, which resulted in a dramatic improvement in pain and function.

Barriers and Best Practices on the Management of Opioid Use Disorder

Opioids refer to chemicals that agonize opioid receptors in the body resulting in analgesia and sometimes, euphoria. Opiates include morphine and codeine; semi-synthetic opioids include heroin, hydrocodone, oxycodone, and buprenorphine; and fully synthetic opioids include tramadol, fentanyl and methadone. In 2021, an estimated 5.6 million individuals met criteria for opioid use disorder. This article provides an overview of the pharmacology of heroin and non-prescription fentanyl (NPF) and its synthetic analogues, and summarizes the literature related to the management of opioid use disorder, overdose, and withdrawal. This is followed by a description of barriers to treatment and best practices for management with a discussion on recent updates and their potential impact on this patient population. This is followed by a description of barriers to treatment and best practices for management with a discussion on recent updates and their potential impact on this patient population.

Overview of best practices for buprenorphine initiation in the emergency department

In recent decades, opioid overdoses have increased dramatically in the United States and peer countries. Given this, emergency medicine physicians have become adept in reversing and managing complications of acute overdose. However, many remain unfamiliar with initiating medication for opioid use disorder such as buprenorphine, a high-affinity partial opioid agonist. Emergency department-based buprenorphine initiation is supported by a significant body of literature demonstrating a marked reduction in mortality in addition to increased engagement in care. Buprenorphine initiation is also safe, given both the pharmacologic properties of buprenorphine that reduce the risk of diversion or recreational use, and previously published literature demonstrating low rates of respiratory depression, sedation, and precipitated withdrawal. Further, barriers to emergency department-based initiation have been reduced in recent years, with publicly available dosing and up-titration schedules, numerous publications overviewing best practices for managing precipitated withdrawal, and removal of USA policies previously restricting patient access and provider prescribing, with the removal of the X-waiver via the Medication Access and Training Expansion Act. Despite reductions in barriers, buprenorphine initiation in the emergency room remains underutilized. Poor uptake has been attributed to numerous individual and systemic barriers, including inadequate education, provider stigma, and insufficient access to outpatient follow-up care. The following practice innovation aims to summarize previously published evidence-based best practices and provide an accessible, user-friendly initiation guide to increase emergency physician comfortability with buprenorphine initiation going forward.

Evaluation of Low-dose Buprenorphine Initiation With Buprenorphine Buccal Films in Hospitalized Patients: A Retrospective Cohort Study

OBJECTIVE

Low-dose buprenorphine initiation (LDBI) strategies to transition patients from full opioid agonists to buprenorphine have previously been described using sublingual films, intravenous solution, transdermal patches, and, more recently, buccal films. The objective of this study was to describe the effectiveness of LDBI using novel titration schedules with buccal films.

METHODS

This is a retrospective cohort study of hospitalized patients with opioid use disorder (OUD) or physiologic dependence to opioids who underwent LDBI with buprenorphine buccal films at NYU Langone Health. Two LDBI protocols were evaluated, including a short titration schedule over 4 days and a long schedule over 7 days. The primary outcomes of interest included LDBI completion rates and incidence of opioid withdrawal.

RESULTS

Forty-two patients underwent 46 LDBIs at NYU Langone Health between October 2020 and April 2022. The cohort comprised patients with OUD (57%), chronic pain with OUD (33%), and chronic pain without OUD (10%). Indications for LDBI most commonly included co-occurring pain precluding discontinuation of full opioid agonists (72%), prior history of precipitated withdrawal (30%), and methadone use (23%). The overall completion rate of LDBI was 78%. Withdrawal was encountered in 33% of patients; however, only 2 patients required LDBI discontinuation as a result. On multivariate analysis, a diagnosis of OUD was independently associated with withdrawal during LDBI.

CONCLUSIONS

Buprenorphine buccal films can successfully be used off-label to facilitate LDBI in the hospital setting. We present 4- and 7-day titration protocols, which were well-tolerated, and provide practical considerations for use.

Buprenorphine for Chronic Pain Management: a Narrative Review

PURPOSE OF REVIEW

The aim of this review is to educate healthcare professionals regarding buprenorphine for the use of opioid use disorder (OUD) as well as for chronic pain management. This review provides physicians and practitioners with updated information regarding the distinct characteristics and intricacies of prescribing buprenorphine.

RECENT FINDINGS

Buprenorphine is approved by the US Food and Drug Administration (FDA) for acute pain, chronic pain, opioid use disorder (OUD), and opioid dependence. When compared to most other opioids, buprenorphine offers superior patient tolerability, an excellent half-life, and minimal respiratory depression. Buprenorphine does have notable side effects as well as pharmacokinetic properties that require special attention, especially if patients require future surgical interventions. Many physicians are not trained to initiate or manage patients on buprenorphine. However, buprenorphine offers a potentially safer alternative for medication management for patients who require chronic opioid therapy for pain or have OUD. This review provides updated information on buprenorphine for both chronic pain and OUD.

A Guide to Expanding the Use of Buprenorphine Beyond Standard Initiations for Opioid Use Disorder

Buprenorphine has become an important medication in the context of the ongoing opioid epidemic. However, complex pharmacologic properties and varying government regulations create barriers to its use. This narrative review is intended to facilitate buprenorphine use-including non-traditional initiation methods-by providers ranging from primary care providers to addiction specialists. This article briefly discusses the opioid epidemic and the diagnosis and treatment of opioid use disorder (OUD). We then describe the basic and complex pharmacologic properties of buprenorphine, linking these properties to their clinical implications. We guide readers through the process of initiating buprenorphine in patients using full agonist opioids. As there is no single recommended approach for buprenorphine initiation, we discuss the details, advantages, and disadvantages of the standard, low-dose, bridging-strategy, and naloxone-facilitated initiation techniques. We consider the pharmacology of, and evidence base for, buprenorphine in the treatment of pain, in both OUD and non-OUD patients. Throughout, we address the use of buprenorphine in children and adolescent patients, and we finish with considerations related to the settings of pregnancy and breastfeeding.

Survey of Buprenorphine Low-dose Regimens Used by Healthcare Institutions

BACKGROUND

Buprenorphine microdosing ("low-dosing") allows for initiation of buprenorphine without requiring patients to endure withdrawal. Case studies suggest its favorable utility as an alternative to conventional buprenorphine induction. However, published regimens vary in duration, dosage forms used, and timing of full opioid agonist discontinuation.

METHODS

This cross-sectional survey study sought to determine how buprenorphine low-dosing is approached by medical institutions across the United States. The primary end point was characterization of inpatient buprenorphine low-dosing regimens. Situations and types of patients in which low-dosing is used and obstacles to institutional protocol development were also collected. An online survey was disseminated through professional pharmacy organizations and personal contacts. Responses were collected over 4 weeks.

RESULTS

Twenty-three unique protocols were collected from 25 institutions. Most protocols used buccal (8 protocols) or transdermal (8 protocols) buprenorphine as first doses before transitioning to sublingual buprenorphine. The most common starting doses were buprenorphine 20 μg/h transdermal, 150 μg buccal, and 0.5 mg sublingual. Patients unable to tolerate conventional buprenorphine induction or those who potentially used fentanyl nonmedically were most likely to be prescribed low-dosing. The most common obstacle to developing an internal low-dosing protocol was lack of existing consensus guidelines.

CONCLUSIONS

Similar to published regimens, internal protocols are variable. Buccal first doses may be used more commonly in practice based on survey results, while transdermal first doses are more commonly reported in publications. More research is needed to determine whether differences in starting formulations impact safety and efficacy of buprenorphine low-dosing in the inpatient setting.

The Howard Street Method: A Community Pharmacy-led Low Dose Overlap Buprenorphine Initiation Protocol for Individuals Using Fentanyl

OBJECTIVES

Buprenorphine treatment significantly reduces morbidity and mortality for people with opioid use disorder. Fear of precipitated withdrawal remains a barrier to starting buprenorphine for patients who use synthetic opioids, particularly fentanyl. We aim to evaluate the development and implementation of a buprenorphine low dose overlap initiation (LDOI) protocol in an urban public health community pharmacy.

METHODS

We performed a retrospective chart review of patients with nonprescribed fentanyl use (N = 27) to examine clinical outcomes of a buprenorphine LDOI schedule, named the Howard Street Method, dispensed from a community pharmacy in San Francisco from January to December 2020.

RESULTS

Twenty-seven patients were prescribed the Howard Street Method. Twenty-six patients picked up the prescription and 14 completed the protocol. Of those who completed the protocol, 11 (79%) reported no symptoms of withdrawal and 3 (21%) reported mild symptoms. Four patients (29%) reported cessation of full opioid agonist use and 10 (71%) reported reduction in their use by the end of the protocol. At 30 days, 12 patients (86%) were retained in care and 10 (71%) continued buprenorphine. At 180 days, 6 patients (43%) were retained in care and 2 (14%) were still receiving buprenorphine treatment.

CONCLUSIONS

We found that a LDOI blister-pack protocol based at a community pharmacy was a viable intervention for starting buprenorphine treatment and a promising alternative method for buprenorphine initiation in an underresourced, safety-net population of people using fentanyl.

Association of Urine Fentanyl Concentration With Severity of Opioid Withdrawal Among Patients Presenting to the Emergency Department

BACKGROUND AND AIMS

Fentanyl is involved in most US drug overdose deaths and its use can complicate opioid withdrawal management. Clinical applications of quantitative urine fentanyl testing have not been demonstrated previously. The aim of this study was to determine whether urine fentanyl concentration is associated with severity of opioid withdrawal.

DESIGN

This is a retrospective cross-sectional study.

SETTING

This study was conducted in 3 emergency departments in an urban, academic health system from January 1, 2020, to December 31, 2021.

PARTICIPANTS

This study included patients with opioid use disorder, detectable urine fentanyl or norfentanyl, and Clinical Opiate Withdrawal Scale (COWS) recorded within 6 hours of urine drug testing.

MEASUREMENTS

The primary exposure was urine fentanyl concentration stratified as high (>400 ng/mL), medium (40-399 ng/mL), or low (<40 ng/mL). The primary outcome was opioid withdrawal severity measured with COWS within 6 hours before or after urine specimen collection. We used a generalized linear model with γ distribution and log-link function to estimate the adjusted association between COWS and the exposures.

FINDINGS

For the 1127 patients in our sample, the mean age (SD) was 40.0 (10.7), 384 (34.1%) identified as female, 332 (29.5%) reported their race/ethnicity as non-Hispanic Black, and 658 (58.4%) reported their race/ethnicity as non-Hispanic White. For patients with high urine fentanyl concentrations, the adjusted mean COWS (95% confidence interval) was 4.4 (3.9-4.8) compared with 5.5 (5.1-6.0) among those with medium and 7.7 (6.8-8.7) among those with low fentanyl concentrations.

CONCLUSIONS

Lower urine fentanyl concentration was associated with more severe opioid withdrawal, suggesting potential clinical applications for quantitative urine measurements in evolving approaches to fentanyl withdrawal management.

Inpatient Low-dose Transitions From Full Agonist Opioids Including Methadone Onto Long-acting Depot Buprenorphine: Case Series From a Multicenter Clinical Trial

OBJECTIVES

Persons with opioid use disorder (OUD) suffer disproportionately from morbidity and mortality related to serious addiction-related infections requiring hospitalization. Long-acting buprenorphine (LAB) is an underused medication for OUD that may facilitate linkage to care and treatment retention when administered before hospital discharge. Transition onto buprenorphine in the inpatient setting is often complicated by pain, active infection management, potential surgical interventions, and risk of opioid withdrawal in transition from full agonists to a partial agonist.

METHODS

The COMMIT Trial is a randomized controlled trial evaluating LAB administered by infectious disease physicians and hospitalists compared with treatment as usual for persons with OUD hospitalized with infections. We report a case series of participants on full agonist opioids including methadone who were transitioned to sublingual buprenorphine using low-dose ( microdosing ) strategies followed by LAB injection.

RESULTS

Seven participants with current opioid use disorder and life-threatening infections, all with significant concurrent pain and many requiring surgical intervention, underwent low-dose transitions starting at buccal buprenorphine doses ranging from 225 μg to 300 μg 3 times a day on the first day. All were well tolerated with average time to LAB injection of 7.5 days (range, 5-10 days).

CONCLUSIONS

Inpatient low-dose buprenorphine transition from full agonist opioids including methadone onto LAB is feasible even in those with complex hospitalizations for concurrent infections and/or surgery. This strategy facilitates dosing of LAB before hospital discharge when risk of opioid relapse and overdose are significant.

Low dose IV buprenorphine inductions for patients with opioid use disorder and concurrent pain: a retrospective case series

BACKGROUND

Hospitalizations are a vital opportunity for the initiation of life-saving opioid agonist therapy (OAT) for patients with opioid use disorder. A novel approach to OAT initiation is the use of IV buprenorphine for low dose induction, which allows patients to immediately start buprenorphine at any point in a hospitalization without stopping full agonist opioids or experiencing significant withdrawal.

METHODS

This is a retrospective case series of 33 patients with opioid use disorder concurrently treated with full agonist opioids for pain who voluntarily underwent low dose induction at a tertiary academic medical center. Low dose induction is the process of initiating very low doses of buprenorphine at fixed intervals with gradual dose increases in patients who recently received or are simultaneously treated with full opioid agonists. Our study reports one primary outcome: successful completion of the low dose induction (i.e. transitioned from low dose IV buprenorphine to sublingual buprenorphine-naloxone) and three secondary outcomes: discharge from the hospital with buprenorphine-naloxone prescription, self-reported pain scores, and nursing-assessed clinical opiate withdrawal scale (COWS) scores over a 6-day period, using descriptive statistics. COWS and pain scores were obtained from day 0 (prior to starting the low dose induction) to day 5 to assess the effect on withdrawal symptoms and pain control.

RESULTS

Thirty patients completed the low dose induction (30/33, 90.9%). Thirty patients (30/33, 90.9%) were discharged with a buprenorphine prescription. Pain and COWS scores remained stable over the course of the study period. Mean COWS scores for all patients were 2.6 (SD 2.8) on day 0 and 1.6 (SD 2.6) on day 5. Mean pain scores for all patients were 4.4 (SD 2.1) on day 0 and 3.5 on day 5 (SD 2.1).

CONCLUSIONS

This study found that an IV buprenorphine low dose induction protocol was well-tolerated by a group of 33 hospitalized patients with opioid use disorder with co-occurring pain requiring full agonist opioid therapy. COWS and pain scores improved for the majority of patients. This is the first case series to report mean daily COWS and pain scores over an extended period throughout a low dose induction process.

Buprenorphine reduces somatic withdrawal in a mouse model of early-life morphine exposure

The rising prevalence of early-life opioid exposure has become a pressing public health issue in the U.S. Neonates exposed to opioids in utero are at risk of experiencing a constellation of postpartum withdrawal symptoms commonly referred to as neonatal opioid withdrawal syndrome (NOWS). Buprenorphine (BPN), a partial agonist at the mu-opioid receptor (MOR) and antagonist at the kappa-opioid receptor (KOR), is currently approved to treat opioid use disorder in adult populations. Recent research suggests that BPN may also be effective in reducing withdrawal symptoms in neonates who were exposed to opioids in utero. We sought to determine whether BPN attenuates somatic withdrawal in a mouse model of NOWS. Our findings indicate that the administration of morphine (10mg/kg, s.c.) from postnatal day (PND) 1-14 results in increased somatic symptoms upon naloxone-precipitated (1mg/kg, s.c.) withdrawal. Co-administration of BPN (0.3mg/kg, s.c.) from PND 12-14 attenuated symptoms in morphine-treated mice. On PND 15, 24h following naloxone-precipitated withdrawal, a subset of mice was examined for thermal sensitivity in the hot plate test. BPN treatment significantly increased response latency in morphine-exposed mice. Lastly, neonatal morphine exposure elevated mRNA expression of KOR, and reduced mRNA expression of corticotropin-releasing hormone (CRH) in the periaqueductal gray when measured on PND 14. Altogether, this data provides support for the therapeutic effects of acute low-dose buprenorphine treatment in a mouse model of neonatal opioid exposure and withdrawal.

Variability in opioid use disorder clinical presentations and treatment in the emergency department: A mixed-methods study

BACKGROUND

There is strong evidence for emergency department (ED)-initiated treatment of opioid use disorder (OUD). However, implementation is variable, and ED management of OUD may differ by clinical presentation. Our aim was to use mixed methods to explore variation in ED-based OUD care by patient clinical presentation and understand barriers and facilitators to ED implementation of OUD treatment across scenarios.

METHODS

We analyzed treatment outcomes in OUD-related visits within three urban, academic EDs from 12/2018 to 7/2020 following the implementation of interventions to increase ED-initiated OUD treatment. We assessed differences in treatment with medications for OUD (MOUDs) by clinical presentation (overdose, withdrawal, others). These data were integrated with results from 5 focus groups conducted with 28 ED physicians and nurses January to April 2020 to provide a richer understanding of clinician perspectives on caring for ED patients with OUD.

RESULTS

Of the 1339 total opioid-related visits, there were 265 (20%) visits for overdose, 123 (9%) for withdrawal, and 951 (71%) for other OUD-related conditions. 23% of patients received MOUDs during their visit or at discharge. Treatment with MOUDs was least common in overdose presentations (6%) and most common in withdrawal presentations (69%, p < 0.001). Buprenorphine was prescribed at discharge in 15% of visits, including 42% of withdrawal visits, 14% of other OUD-related visits, and 5% of overdose visits (p < 0.001). In focus groups, clinicians highlighted variation in ED presentations among patients with OUD. Clinicians also highlighted key aspects necessary for successful treatment initiation including perceived patient receptivity, provider confidence, and patient clinical readiness.

CONCLUSIONS

ED-based treatment of OUD differed by clinical presentation. Clinician focus groups identified several areas where targeted guidance or novel approaches may improve current practices. These results highlight the need for tailored clinical guidance and can inform health system and policy interventions seeking to increase ED-initiated treatment for OUD.

Opioids and Opioid Use Disorder in Pregnancy

Overdose is a leading cause of pregnancy-associated morbidity and mortality in the United States. As such, all obstetric providers have a responsibility to provide evidence-based care for patients with opioid use disorder to mitigate adverse outcomes associated with substance use during pregnancy.

48-hour Induction of Transdermal Buprenorphine to Sublingual Buprenorphine/Naloxone: The IPPAS Method

Buprenorphine is an effective medication for the treatment of opioid use disorder. However, the traditional method of buprenorphine induction requires a period of abstinence and the development of at least moderate withdrawal, which can be barriers in starting treatment. We present the case of a hospitalized patient with opioid use disorder using unregulated fentanyl, who underwent a transdermal buprenorphine induction over 48 hours to initiate sublingual buprenorphine/naloxone on the third day. The patient experienced minimal levels of withdrawal and did not experience precipitated withdrawal. The ease of use of this novel induction method over previously published induction protocols can greatly improve the accessibility of buprenorphine for patients and healthcare staff.

Top Ten Tips Palliative Care Clinicians Should Know About Buprenorphine

Pain management in palliative care (PC) is becoming more complex as patients survive longer with life-limiting illnesses and population-wide trends involving opioid misuse become more common in serious illness. Buprenorphine, a generally safe partial mu-opioid receptor agonist, has been shown to be effective for both pain management and opioid use disorder. It is critical that PC clinicians become comfortable with indications for its use, strategies for initiation while understanding risks and benefits. This article, written by a team of PC and addiction-trained specialists, including physicians, nurse practitioners, social workers, and a pharmacist, offers 10 tips to demystify buprenorphine use in serious illness.

Adapting low-dose buprenorphine induction to meet patient needs: A pilot study

Introduction

Low-dose buprenorphine induction (LDBI) has been proposed to initiate buprenorphine in patients who are taking full opioid agonists in order to limit the risk of precipitated withdrawal. The objective of this study was to understand how real-world patient-specific adjustments in LDBI protocols impacted success rates in buprenorphine conversion.

Methods

This case series identified patients seen by the Addiction Medicine Consult Service at UPMC Presbyterian Hospital who were started on LDBI with transdermal buprenorphine followed by sublingual buprenorphine-naloxone between April 20, 2021, and July 20, 2021. The primary outcome was successful induction of sublingual buprenorphine. Characteristics of interest included total morphine milligram equivalents (MME) in the 24 hours prior to induction, MME during each day of induction, total time of induction, and final daily maintenance buprenorphine dose.

Results

Of the 21 patients included for analysis, 19 (91%) successfully completed LDBI and converted to a maintenance buprenorphine dose. Median (IQR) opioid analgesia utilization in the 24 hours prior to induction was 113 MME (63-166 MME) in the converted group and 83 MME (75-92 MME) in the group that did not convert.

Conclusions

Transdermal buprenorphine patch followed by sublingual buprenorphine-naloxone resulted in a high success rate for LDBI. Patient-specific adjustments may be considered in order to effect a high success rate of conversion.

Rapid Overlap Initiation Protocol Using Low Dose Buprenorphine for Opioid Use Disorder Treatment in an Outpatient Setting: A Case Series

OBJECTIVES

Fear and risk of precipitated withdrawal are barriers for initiating buprenorphine in individuals with opioid use disorder, particularly among those using fentanyl. A buprenorphine rapid overlap initiation (ROI) protocol (also knownas "rapidmicro-dosing") utilizing small, escalating doses of buprenorphine can overcome this barrier, reaching therapeutic doses in 3 to 4 days. We sought to demonstrate the feasibility of implementing a buprenorphine ROI protocol for buprenorphine initiation in the outpatient setting.

METHODS

We conducted a retrospective chart review of patients prescribed an outpatient ROI protocol at the Office-based Buprenorphine Induction Clinic from October to December 2020. The ROI protocol utilizes divided doses of sublingual buprenorphine tablets and blister packaging for easier dosing. Patients were not required to stop other opioid use and were advised to follow up on day 4 of initiation.

RESULTS

Twelve patients were included, of whom eleven (92%) were using fentanyl at intake. Eleven patients picked up their prescription. Seven patients returned for follow-up (58%), and all 7 completed the ROI protocol. One patient reported any withdrawal symptoms, which were mild. At 30 days, 7 patients (58%) were retained in care, and 5 (42%) were still receiving buprenorphine treatment, 4 (33%) of whom had been abstinent from nonprescribed opioid use for ≥2 weeks.

CONCLUSIONS

The ROI protocol was successful in initiating buprenorphine treatment for patients in our outpatient clinic, many of whom were using fentanyl. The ROI protocol may offer a safe alternative to traditional buprenorphine initiation and warrants further study.

Management of opioid withdrawal and initiation of medications for opioid use disorder in the hospital setting

Opioid use disorder (OUD) has become increasingly prevalent among hospitalized patients in the United States and globally. As its prevalence increases, this provides a valuable opportunity for clinicians in the hospital setting to engage and initiate management and treatment of OUD. This article aims to provide hospitalists and other clinicians working in the hospital with a narrative review of the management of opioid withdrawal and the initiation of medications for opioid use disorder (MOUD) in the hospital and provide an update on a novel low dose approach to buprenorphine induction (also commonly referred to as the "microinduction" method). Management can initially include treating withdrawal symptoms with opioids as well as with a combination of non-opioid medications such as alpha 2 agonists, benzodiazepines, and/or antiemetics as needed. Besides simply managing withdrawal symptoms, clinicians can further improve the care of patients with OUD through initiating maintenance treatment with MOUD, ideally with opioids used in the initial management of withdrawal. Opioid detoxification is an inferior method of primary treatment and is associated with relapse and poor outcomes. In contrast, treatment with MOUD using methadone or buprenorphine is associated with superior treatment outcomes and reduced relapse compared to detoxification alone. Treatment with MOUD using methadone or buprenorphine can be successfully used in the hospital setting. A novel low dose approach to buprenorphine induction may be useful in minimizing precipitated withdrawals in patients who have recently used or received opioids, which makes this an attractive option in the hospital where patients are frequently on opioids for acutely painful conditions. The hospital setting also provides a valuable opportunity for clinicians to address harm reduction in patients with OUD. Finally, clinicians can improve the long-term outcomes of patients with OUD by ensuring a smooth discharge with adequate and timely follow-up.

Community based buprenorphine micro-induction in the context of methadone maintenance treatment and fentanyl - Case report

INTRODUCTION

The micro-induction method of initiating buprenorphine is becoming a popular method for initiating buprenorphine in patients with Opioid Use Disorder, who are on full opioid agonists, either prescribed or non-prescribed, in order to avoid precipitated withdrawal. Given the rising concerns around illicit fentanyl use, this method of initiating buprenorphine has become another tool for clinicians to help patients with Opioid Use Disorder, even when multiple full opioid agonists are involved. While the process for initiating buprenorphine through this process is well studied, the characteristics of patients who are able to tolerate this initiation method in an outpatient setting is not.

CASE(S)

We present the cases of two patients with Opioid Use Disorder in a community-based methadone maintenance program in whom micro-induction methods were used to initiate buprenorphine without lowering the methadone dose. Both patients successfully transitioned to buprenorphine without precipitated withdrawal. One of the patients was also using fentanyl at the time of induction and was able to abstain from fentanyl use following the induction process.

CONCLUSION

Initiating Buprenorphine using micro-induction strategies in a community based outpatient clinic in patients who are already on full opioid agonists is feasible, in these particular cases, the methadone dose or concurrent fentanyl use did not affect the outcome. We present the characteristics of the patient and the community clinic hoping that this helps more clinicians in replicating this induction strategy.

Transdermal buprenorphine for in-hospital transition from full agonist opioids to sublingual buprenorphine: a retrospective observational cohort study

INTRODUCTION

Patients with opioid use disorder may have difficulty transitioning from full-agonist opioids to sublingual buprenorphine due to the risk of precipitated opioid withdrawal. Novel strategies have been developed to facilitate this transition, including the use of micro-dosing with transdermal buprenorphine. We began using a transdermal buprenorphine transition strategy at our hospital in 2019.

METHODS

We performed a retrospective observational cohort study of patients treated with transdermal buprenorphine to facilitate transition from full-agonist opioids (prescribed or recreational) while hospitalized between January 2019 and December 2020. Patients were excluded if transdermal buprenorphine was given for pain, if they did not receive at least one dose of sublingual buprenorphine while hospitalized, or if their clinical course precluded analysis of their tolerance of the transition protocol. Data on the doses and timing of medications, symptoms during transition, and hospital outcomes were abstracted from the electronic medical record.

RESULTS

We identified 41 cases that satisfied inclusion and exclusion criteria. Thirty-five cases involved a transition from medically indicated opioids; of these, 8 cases involved a transition from methadone. Six cases involved a transition from illicit opioids used prior to hospital presentation. For patient transitioning from medically indicated opioids, the median milligram morphine equivalent (MME) on the day prior to transdermal buprenorphine application was 63.8 (range 0-900, IQR 153.8) and the median MME on the day of transdermal buprenorphine application was 34.5 (range 0-600, IQR 65.3). The median initial dose of sublingual buprenorphine administered was 8 mg (range 2-8mg, IQR 6mg), the median total first-day dose was 16mg (range 2-24mg, IQR 16mg), and the median total daily dose on the last day of follow-up was 16mg (range 2-24mg, IQR 16mg). In 38 cases, patients completed the transition to sublingual buprenorphine and were still taking buprenorphine at the time they left the hospital. The transition protocol was fairly well-tolerated, with 59% of cases tolerating it well and 32% tolerating it fairly.

DISCUSSION

Our findings suggest that the use of transdermal buprenorphine to facilitate transition to sublingual buprenorphine is generally well-tolerated, and may be helpful in hospitalized patients. We identified several areas for improvement in future practice by reviewing the clinical courses of patients who tolerated transition poorly. Limitations of the study include its retrospective chart review design, the lack of a standardized transition protocol during the study period, and the lack of standardized data in the medical record regarding patients' tolerance of the transition protocol. Future research should include prospective studies using a standardized protocol and structured, pre-planned assessments of opioid withdrawal during the transition period.

CONCLUSION

The use of transdermal buprenorphine to facilitate induction of sublingual buprenorphine therapy in hospitalized patients with OUD was generally well-tolerated in this single-center retrospective observational study. Further prospective research is needed to demonstrate efficacy and optimize treatment protocols.

Buprenorphine Microdosing for the Pain and Palliative Care Clinician

Buprenorphine (BUP) can be a safe and effective alternative to traditional opioids for many patients with chronic pain. For patients on higher doses of opioids, rotation to BUP is complicated by the requirement of an opioid-free interval or withdrawal during the transition. Microdosing inductions, in which BUP is gradually titrated, while full agonist opioids are continued, are a viable alternative to traditional inductions. The objective of this article is to review the current literature on BUP microdosing induction, with a focus on patients using opioids for pain. A literature review of the PubMed database was performed in the United States on articles published from inception to May 2021. A total of 34 publications were included. The most commonly utilized microdosing strategy involved administering divided doses of sublingual (SL) products marketed for opioid use disorder treatment, with 25 (73.5%) articles reporting use of partial SL tablets or films (ranging from 1/8 to 1/2 of a 2 mg product) at some point during the induction. Transdermal patches, low-dose SL BUP available in Europe, intravenous BUP, and buccal BUP have also been used. Beyond the products used, the speed of the microinduction, setting, final BUP dosing, and management of concomitant full agonists vary widely in the literature. Microdosing regimens should be individualized based on local guidelines and patient-specific factors. Further studies comparing the safety and efficacy of different protocols are warranted.

Low Dose Initiation of Buprenorphine: A Narrative Review and Practical Approach

Low dose buprenorphine initiation, is an alternative method of initiating buprenorphine in which the starting dose is very low and gradually increased to therapeutic levels over a period of days. This method takes advantage of slow displacement of the full opioid agonist from mu-opioid receptors, avoiding the need for a person with opioid use disorder to experience opioid withdrawal symptoms before initiating buprenorphine, while also minimizing the risk of precipitated opioid withdrawal. With this initiation method, full opioid agonists can be continued as buprenorphine is initiated, expanding the population to which buprenorphine can be offered. To date, the literature on low dose initiation is primarily case-based but rapidly growing. While evidence emerges, guidance for the use of low dose initiation is clearly desired and urgently needed in the context of an increasingly risky and contaminated opioid drug supply, particularly with high potency synthetic opioids, driving overdose deaths. Despite limited evidence, several principles to guide low dose initiation have been identified including: (1) choosing the appropriate clinical situation, (2) initiating at a low buprenorphine dose, (3) titrating the buprenorphine dose gradually, (4) continuing the full opioid agonist even if it is nonmedical, (5) communicating clearly with frequent monitoring, (6) pausing or delaying buprenorphine dose changes if opioid withdrawal symptoms occur, and (7) prioritizing care coordination. We review a practical approach to low dose initiation in hospital-based and outpatient settings guided by the current evidence.

Synergistic Effect of Ketamine and Buprenorphine Observed in the Treatment of Buprenorphine Precipitated Opioid Withdrawal in a Patient With Fentanyl Use

BACKGROUND

Optimal treatment of buprenorphine precipitated opioid withdrawal (BPOW) is unclear. Full agonist treatment of BPOW is limited by buprenorphine's high-affinity blockade at mu-opioid receptors (μORs). Buprenorphine's partial agonism (low intrinsic efficacy) at μORs can limit the effectiveness of even massive doses once BPOW has begun. Adjunct medications, such as clonidine, are rarely effective in severe BPOW. Ketamine is an N-methyl-D-aspartate receptor antagonist with a potentially ideal pharmacologic profile for treatment of BPOW. Ketamine reduces opioid withdrawal symptoms independently of direct μOR binding, synergistically potentiates the effectiveness of buprenorphine μOR signaling, reverses (resensitizes) fentanyl induced μOR receptor desensitization, and inhibits descending pathways of hyperalgesia and central sensitization. Ketamine's rapid antidepressant effects potentially address depressive symptoms and subjective distress that often accompanies BPOW. Ketamine is inexpensive, safe, and available in emergency departments. To date, neither ketamine as treatment for BPOW nor to support uncomplicated buprenorphine induction has been described.

CASE DESCRIPTION

We report a case of an illicit fentanyl-using OUD patient who experienced severe BPOW during an outpatient low-dose cross taper buprenorphine induction (ie, "microdose"). The BPOW was successfully treated in the emergency department with a combination of ketamine (0.6 mg/kg intravenous over 1 hour) combined with high-dose buprenorphine (16 mg sublingual single dose); 3 days later he was administered a month-long dose of extended-release subcutaneous buprenorphine which was repeated monthly (300 mg). At 90 days the patient remained in treatment and reported continuous abstinence from fentanyl use.

CONCLUSIONS

This single case observation raises important questions about the potential therapeutic role of ketamine as a treatment for BPOW. BPOW is an important clinical problem for which there is currently only limited guidance and no universally accepted approach. Prospective study comparing the effectiveness of differing pharmacologic approaches to treat BPOW is urgently needed.

Opioid-induced analgesia among persons with opioid use disorder receiving methadone or buprenorphine: A systematic review of experimental pain studies

BACKGROUND

Treating acute pain among persons with opioid use disorder (OUD) on opioid agonist therapy (OAT) is complex, and the therapeutic benefits of opioids remain unclear when weighted against their abuse potential and respiratory depressant effects.

METHODS

We conducted a systematic review of experimental pain studies examining opioid-induced analgesia among persons with OUD on OAT. We searched multiple databases from inception to July 30, 2021. Study quality was assessed by previously established validity measures.

RESULTS

Nine studies were identified, with a total of 225 participants, of whom 63% were male, and 37% were female. Six studies included methadone-maintained persons with OUD; four studies included buprenorphine-maintained persons with OUD; and three studies included healthy persons as comparison groups. Either additional doses of OAT or other opioids - morphine, oxycodone, hydromorphone, or remifentanil - were administered. In seven studies, persons with OUD on OAT did not experience analgesia, despite receiving opioid doses up to 20 times greater than those clinically used to treat severe pain among the opioid naïve. Conversely, in two studies, high-potency opioids did produce analgesia, albeit with greater abuse potential. Notably, persons with OUD on OAT remained vulnerable to respiratory depression.

CONCLUSIONS

Although persons with OUD on OAT can derive analgesic effects from opioids, high-potency compounds may be required to achieve clinically significant pain relief. Further, persons with OUD on OAT may remain vulnerable to opioid-induced abuse potential and respiratory depression. Together, these finding have clinical, methodological, and mechanistic implications for the treatment of acute pain in the context of OAT.