Transition From Methadone to Buprenorphine Using a Short-acting Agonist Bridge in the Inpatient Setting: A Case Study

Low-dose buprenorphine initiation and treatment continuation among hospitalized patients with opioid dependence: A retrospective cohort study

BACKGROUND

Buprenorphine is an effective treatment for both opioid use disorder (OUD) and chronic pain, but buprenorphine's pharmacology complicates treatment initiation for some patients. Low-dose buprenorphine initiation is a novel strategy that may reduce precipitated withdrawal. Few studies describe what patient populations benefit most from low-dose initiations and the clinical parameters that impact treatment continuation. This study aimed to 1) describe experiences with low-dose buprenorphine initiation, including both successes and failures among hospitalized patients in an urban underserved community; 2) identify patient- and treatment-related characteristics associated with unsuccessful initiation and treatment discontinuation; and 3) assess buprenorphine treatment continuation after discharge.

METHODS

This is a retrospective cohort study with opioid-dependent (meaning OUD or receiving long-term opioid therapy for chronic pain) patients who underwent low-dose buprenorphine initiation during hospital admission from October 2021 through April 2022. The primary outcome was successful completion of low-dose initiation. Bivariate analysis identified patient- and treatment-related factors associated with unsuccessful initiation. Secondary outcomes were buprenorphine treatment discontinuation at post-discharge follow-up, 30- and 90-days.

RESULTS

Of 28 patients who underwent low-dose buprenorphine initiation, 68 % successfully completed initiation. Unsuccessful initiation was associated with receipt of methadone during admission and higher morphine milligram equivalents (MME) of supplemental opioids. Of 22 patients with OUD, the percent receiving a buprenorphine prescription at a follow-up visit, 30 days, and 90 days, respectively, was 46 %, 36 %, and 36 %. Of 6 patients with chronic pain, the percent receiving a buprenorphine prescription at a follow-up visit, 30 days, and 90 days, respectively, was 100 %, 100 %, and 83 %.

CONCLUSION

Low-dose buprenorphine initiation can be successful in opioid-dependent hospitalized patients. Patients taking methadone or requiring higher MME of supplemental opioids may have more difficulty with the low-dose buprenorphine initiation approach, but these findings should be replicated in larger studies. This study suggests patient- and treatment-related factors that clinicians could consider when determining the optimal treatment strategy for patients wishing to transition to buprenorphine.

Transitioning From High-dose Methadone to Buprenorphine Using a Microdosing Approach: Unique Considerations at ASAM Level 3 Facilities

Transitions from high-dose methadone to buprenorphine for treatment of opioid use disorder (OUD) present risk of precipitated withdrawal related to the introduction of a high-affinity partial agonist at the mu-opioid receptor after occupancy by a lower-affinity full agonist. Various strategies have been explored to maintain patient stability during this process, including microdosing buprenorphine. Current literature lacks consensus on an optimal setting and strategy for initiating a buprenorphine microdosing protocol and gives little detail on patients' conditions after the acute transition period. We report a 6-day microdosing transition from methadone 100 mg directly to sublingual buprenorphine, followed by a 20-day period of monitoring and additional treatment. This patient tolerated a sublingual buprenorphine microdosing protocol while using supportive medications with a peak Clinical Opiate Withdrawal Scale score of 6. The patient's most significant withdrawal symptoms occurred several days after completion of the microdosing process. This case demonstrates the feasibility of using a transmucosal buprenorphine formulation in microdosing transitions from high-dose methadone directly to buprenorphine, and highlights the utility of a medically monitored intensive inpatient setting (American Society of Addiction Medicine level 3.7) in providing appropriate monitoring and treatment during and after a microdosing transition.

Developing A Rapid Transfer from Opioid Full Agonist to Buprenorphine: "Ultrarapid Micro-Dosing" Proof of Concept

Buprenorphine/naloxone has been shown to be effective for treating opioid use disorder (OUD). However, the traditional method of induction requires a patient to be in moderate-to-severe withdrawal, which is challenging, time-consuming, and a common reason for leaving against medical advice. Induction strategies that minimize the severity and duration of patient discomfort while enabling patients to reach therapeutic doses during short hospital admissions can mitigate difficulties when inducing a patient on buprenorphine/naloxone. This case-series illustrates two patients with OUD using illicit fentanyl, who were successfully started on buprenorphine/naloxone using 24-hour and 6-hour micro-dosing induction protocol. During induction, the patients were up-titrated to a therapeutic dose through ultrarapid micro-dosing with ongoing use of short-acting opioids. Both patients reached therapeutic doses experiencing minimal levels of withdrawal. This case-series is a proof of concept for the use of a buprenorphine/naloxone ultrarapid micro-induction protocol for inpatients with OUD. By reducing the length of induction and precluding the need for withdrawal, this method offers several advantages over previously published inductions protocols and can improve the accessibility of buprenorphine/naloxone to patients with OUD.

Microinduction to Buprenorphine from Methadone for Chronic Pain: Outpatient Protocol with Case Examples

The negative sequelae of full mu agonist chronic opioid analgesic therapy (COAT) are numerous and well documented. One safer alternative to COAT use in chronic, non-cancer pain (CNCP) is a transition to buprenorphine. However, transitioning patients from methadone COAT regimens can be challenging due to the pharmacodynamics of buprenorphine, as well as to the limited commercial formulations of buprenorphine available, and their restrictive instructions for use. Presented here are clinical cases transitioned to buprenorphine from methadone via a novel microinduction protocol during enrollment in an outpatient, group, integrative, multidisciplinary program. The protocol was successful to promote satisfactory and sustained COAT cessation for patients with CNCP and is arguably safer than current conventional practices.

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.

Transition From Full Mu Opioid Agonists to Buprenorphine in Opioid Dependent Patients-A Critical Review

Methadone, a full opioid agonist at the mu-, kappa-, and delta-receptor, and buprenorphine, a partial agonist at the mu receptor, are first-line medications in opioid maintenance treatment. Transition from methadone to buprenorphine may precipitate withdrawal, and no accepted algorithm for this procedure has been developed. Current treatment strategies recommend transfer from methadone to buprenorphine predominantly in patients at low doses of methadone (30-40 mg/day). There are some reports indicating that transition from higher doses of methadone may be possible. A number of dosing strategies have been proposed to soften withdrawal symptoms and facilitate transfer including use of other opioids or medications and especially microdosing techniques for buprenorphine. The case series and studies available thus far are reviewed.

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

BACKGROUND

Opioid withdrawal symptoms prior to buprenorphine initiation may be intolerable and as a result, alternative strategies have emerged. We aim to systematically review the efficacy and safety of buprenorphine initiation that aims to omit prerequisite withdrawal.

METHODS

We conducted a systematic literature search of MEDLINE and CENTRAL from 1996 through April 10, 2020, augmented with searches in Google Scholar and www.clinicaltrials.gov . A study was included if it was in patients with substance use disorder or chronic pain that were taking a full mu opioid agonist and transitioning 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

We included 15 case reports/series, reporting 24 unique cases, in our qualitative synthesis. No controlled studies were identified. Microdosing and bridging with a buprenorphine patch were the most common strategies reported. Transition to buprenorphine with complete cessation of opioid agonists was achieved in 87.5% (n = 21) of cases. Withdrawal during initiation occurred in 58.3% (n = 14) of cases, two of which were at least moderate in severity.

CONCLUSION

Buprenorphine initiation strategies that omit prerequisite withdrawal have emerged. Low quality evidence from case reports suggests withdrawal during initiation is common but most often mild in severity. There is an unmet need for controlled studies to inform their efficacy and safety compared with traditional strategies, including outcomes during initiation and in the long-term.

The Pharmacology of Buprenorphine Microinduction for Opioid Use Disorder

Although expanding the availability of buprenorphine—a first-line pharmacotherapy for opioid-use disorder (OUD)—has increased the capacity of healthcare systems to offer treatment, starting this medication is fraught with significant barriers. Standard induction regimens require persons with OUD to taper and discontinue full opioid agonists and experience opioid withdrawal prior to the first dose of buprenorphine. Further, emerging evidence indicates that precipitated withdrawal during induction may impact long-term treatment outcomes. Microinduction is a novel approach that, by harnessing buprenorphine’s unique pharmacological profile, may allow circumventing the needed for prolonged opioid tapers, and reduce the risk of precipitated withdrawal—holding promise to enhance treatment access. In this review, we examine the pharmacological basis for microinduction and appraise the evidence of this approach to improve clinical outcomes among persons with OUD. First, we highlight the potential dose-dependent effects of buprenorphine on two key neuroadaptations at the mu-opioid receptor (MOR)—resensitization and upregulation. We then focus on how microinduction may reverse these chronic MOR neuroadaptations, allowing the maintenance of an adequate opioid tone, and thereby potentially circumventing opioid withdrawal. Second, we describe the clinical evidence available, derived from observational reports and open-label studies, examining the potential efficacy of microinduction. Despite significant heterogeneity—exemplified by variable buprenorphine formulations, daily doses, and schedules of administration—these data provide preliminary support for the feasibility of microinduction. Finally, we provide new mechanistic, methodological, and clinical insights to guide future translational research, as well as randomized, placebo-controlled clinical trials in this compelling agenda of pharmacotherapy development.

Micro-dosing Intravenous Buprenorphine to Rapidly Transition From Full Opioid Agonists

For patients with opioid use disorder transitioning from methadone or requiring opioid analgesia, initiating buprenorphine for opioid use disorder can be difficult because of the risk of precipitated withdrawal. Low-dose initiation, also known as micro-dosing, is an alternative to standard initiation. Prior studies relied on nonstandard dosing of tablets or films, patches, or buccal formulations, all of which are unavailable in many hospitals. We report a novel approach to micro-dosing using intravenous buprenorphine. Two patients, one on methadone maintenance and another requiring postoperative opioid analgesia, were transitioned to buprenorphine with concurrent full-agonist opioids and without precipitated withdrawal.