(51) Extended-Release Injectable Buprenorphine For Same-Day Induction – A Case Series

Background & Introduction: Fentanyl and Fentanyl Analogues (FFA) are a cause of increasing overdose deaths in the United States (1). Medications for opioid use disorder (MOUD) including extended-release buprenorphine (XRB) are part of an evidence-based strategy to decrease morbidity and mortality in patients with opioid use disorder (OUD). The current manufacturer’s prescribing information recommends XRB administration only after initiating treatment with a buprenorphine-containing product. Case reports and initial trials have demonstrated protocols with shorter sublingual (SL) lead-in (2) or supervised induction (3) but to our knowledge none have examined the use of XRB without SL lead-in in the outpatient setting.


Outpatient induction using SL buprenorphine often leads to multiple cycles of aborted induction attempts, due to loss to follow-up for multiple reasons (e.g., transportation, employment, housing instability, lost and stolen medications, etc.), leaving patients unable to meet their treatment goals. Novel induction strategies are needed to assist patients in completing buprenorphine induction in the setting of FFA use. We present two cases of patients who underwent buprenorphine induction on the same day as last FFA use utilizing only XRB demonstrating safety and efficacy of XRB for initiation within the low barrier outpatient setting.

Case Description: Case #1:

A 46-year-old female presented to an outpatient clinic after two previous unsuccessful induction attempts of sublingual buprenorphine inductions in the month prior to this visit. Daily FFA use ranged from smoking 4 - 25 pressed tablets. Last use of FFA on the day of XRB was 3-4 hours prior to the visit. Patient had previous documented tolerance of buprenorphine without side effects. Baseline urine drug screen (UDS) was negative for buprenorphine. 300mg XRB was administered subcutaneously. Within two hours of XRB, the patient reported worsening of withdrawal symptoms with the worst symptoms (vomiting, diarrhea, muscle cramps, and restless legs) experienced at 48 hours after injection. Patient continued to smoke FFA during the first 48 hours after injection, then self-tapered FFA use as withdrawal symptoms improved. Patient noted complete resolution of withdrawal symptoms 72 hours post XRB injection. Patient reported use of additional supplemental SL buprenorphine up to 40mg daily during the first 72 hours after XRB injection for breakthrough cravings. Notably, patient did not experience oversedation, or other side effects, despite taking additional buprenorphine SL and continuing to utilize FFA throughout induction.



Case #2:

A 37-year-old male presented to an outpatient clinic after two unsuccessful outpatient SL buprenorphine induction attempts, as well as recent hospital admission for inpatient opioid withdrawal management. Daily FFA use reported ranged from smoking 10 - 25 pressed tablets daily. Last use of FFA on the day of XRB was one hour prior to injection. Patient had previous documented tolerance of buprenorphine without side effects. Baseline UDS was negative for buprenorphine. Patient reported no withdrawal symptoms at the time of XRB injection. Patient continued to smoke FFA pressed tabs throughout the first 24 hours following induction at his baseline daily use. Patient reported onset of withdrawal symptoms 24 hours after XRB. Patient continued his pattern of daily FFA use until 72 hours after XRB, at which time withdrawal symptoms and cravings for FFA had resolved and FFA use was discontinued.

Conclusion & Discussion: Both patients included in this case series had prior experience with SL buprenorphine for induction and expressed frustration with return to fentanyl use within the first 24 – 48 hours following current evidence based induction methods. After patient centered discussion explaining the peak effect of XRB within the first 24 – 48 hours (4), and informing of an expected clinically significant level of buprenorphine through at least the first two weeks following XRB injection, both patients desired this pathway to buprenorphine induction that was protective against early return to use. Patients expressed satisfaction with the novel induction method both because it allowed them to meet their goals of abstinence from FFA, and because it was a method they had chosen after extensive discussion with provider and shared decision making.



While this case series is small, it can inform addiction providers of some of the experiences of this novel induction method including patient reported period of worsened withdrawal symptoms which occurred throughout the the first 24-48 hours after induction. Additional barriers that should be considered are the expense of the medication itself, limitations of insurance coverage, and the current availability of only one manufacturer with only two dosage options.

References: 1) Mattson CL, Tanz LJ, Quinn K, Kariisa M, Patel P, Davis NL. Trends and Geographic Patterns in Drug and Synthetic Opioid Overdose Deaths — United States, 2013–2019. MMWR Morb Mortal Wkly Rep 2021;70:202–207. DOI: https://dx.doi.org/10.15585/mmwr.mm7006a4.
2) Mariani JJ, Mahony AL, Podell SC, Brooks DJ, Brezing C, Luo SX, Naqvi NH, Levin FR. Open-label trial of a single-day induction onto buprenorphine extended-release injection for users of heroin and fentanyl. Am J Addict. 2021 Sep;30(5):470-476. doi: 10.1111/ajad.13193. Epub 2021 Jul 5. PMID: 34223681; PMCID: PMC8459386.
3) Howard Hassman, Stephanie Strafford, Sunita N. Shinde, Amy Heath, Brent  Boyett & Robert L. Dobbins (2022): Open-label, rapid initiation pilot study for extended-release  buprenorphine subcutaneous injection, The American Journal of Drug and Alcohol Abuse, DOI:  10.1080/00952990.2022.2106574 .
4) Sublocade full prescribing information. Revised 9/2023. Accessed on 10/4/2023 https://www.sublocade.com/Content/pdf/prescribing-information.pdf