Serious treatment-emergent adverse events in chronic low back pain patients treated with buprenorphine or oral opioids: a retrospective commercial claims analysis.

Aim: Explore the safety of Belbuca® (buprenorphine buccal film), buprenorphine transdermal patches and oral opioids for chronic low back pain (cLBP) treatment. Methods: The retrospective analysis of the MarketScan Commercial database (2018-2021) included treatment-naive cLBP adults. The first date of buprenorphine (Belbuca and transdermal patch) or opioid prescription was index date. Cohorts were defined based on the index medication. Observation included a 6-month pre-index period, while post-index lasted until the end of continuous insurance coverage. There were 44 relevant treatment-emergent adverse events (TEAEs) identified in the literature. Incidence rate ratio (IRR) and incidence rate difference (IRD) were used to compare serious TEAE rates (in 1000 person-years) between cohorts. Propensity-score matching minimized the selection bias. Results: Buprenorphine had lower rates of 15 serious TEAEs than oral opioids (all p ≤ 0.037), while higher rates only for serious dizziness (IRR 2.44, p = 0.011; driven by Belbuca), opioid abuse/dependence (IRR 3.13, p = 0.004; driven by patches) and cholecystitis (IRD 20.25, p = 0.044; an outlier). Additionally, a comparison between Belbuca and oral opioids showed lower rates of 13 serious TEAEs (all p ≤ 0.024) and a higher serious dizziness rate (IRR 3.17, p = 0.024). Although the rates of serious opioid abuse/dependence were similar (24.60 vs 26.93, p = 0.921), all Belbuca patients and none of the opioid patients had a positive history of these events. Belbuca also had lower rates of five serious TEAEs than transdermal patches (all p ≤ 0.018), including a serious opioid abuse/dependence (IRR 0.04, p < 0.001), but higher rates of serious cholecystitis (IRD 52.17, p = 0.035; an outlier) and suicidal ideation (IRD 156.50, p < 0.001; an outlier). Conclusion: Buprenorphine had a better safety profile than oral opioids in cLBP treatment. Belbuca showed a more favorable TEAE profile than buprenorphine transdermal patches and oral opioids.