An Australian retrospective observational cohort comparison of the use of long-acting injectable buprenorphine products

Abstract

IntroductionIn early 2019, Australia became the first jurisdiction to have two brands of long-acting injectable buprenorphine (LAI-B) products available. Previously published studies have mostly followed pre-planned dosing schedules and seldom compared use of both products. This study presents a retrospective analysis of the “real-world” dosing requirements of patients on LAI-B. MethodFive clinics provided data for patients commenced on LAI-B between 1 February 2019 and 30 June 2021 for buprenorphine doses and intervals between dosing. The study recorded basic demographic data including age, gender, and previous dose of transmucosal buprenorphine. The Local Institutional Ethics Committee provided approval. ResultsOver 3600 individual doses (59 % Buvidal® & 41 % Sublocade®) were administered to 340 individual patients (median age 40 years, 63 % male), with the longest duration in treatment of 856 days. Median estimated duration of a treatment episode was 16.5 months (95%CI: 14.3–19.1). Approximately 94 % transferred from transmucosal buprenorphine (median daily dose 16 mg, range 2-32 mg). Most common LAI-B doses were Sublocade® 100 mg (22.4 %) and Buvidal® Monthly 128 mg (21.5 %); Buvidal® Weekly 24 mg (0.8 %) was least used. 13 % transitioned between LAI-B products. Weekly dose intervals were a median 7 days and monthly doses were given a median of 28 days apart. Overall, 36 % discontinued LAI-B before the census date. Discussions and conclusionsMost patients who started LAI-B remained in treatment, with similar rates in both products. A small, but appreciable number of people switched brands, suggesting that it remains important to have treatment options available.