Evaluation of opioid use disorder treatment outcomes in patients receiving split daily versus once daily dosing of buprenorphine-naloxone

Introduction: In clinical practice, sublingual (SL) buprenorphine-naloxone is prescribed as once daily or split daily dosing for the management of opioid use disorder (OUD). Evidence is lacking that assesses how split daily buprenorphine-naloxone affects OUD outcomes. This study aims to evaluate how the dosing frequency of SL buprenorphine-naloxone impacts therapy effectiveness when treating patients with OUD.Methods: This retrospective analysis included adult outpatients prescribed treatment with SL buprenorphinenaloxone for OUD between July 1, 2016, and March 1, 2020. The study excluded patients with sickle cell disease, recent methadone treatment, or pregnancy. We characterized study groups by dosing frequency, either once daily or split dosing. The study compared retention in treatment, medication adherence, adherence to treatment program, and hospital encounters between groups.Results: The study screened eight-hundred and seven patients, and included 250 patients newly prescribed SL buprenorphine-naloxone. Fifty-seven patients (22.8 %) were prescribed once daily dosing and 193 patients (77.2 %) were prescribed split daily dosing. The study found no significant differences noted in 12-month rates of treatment retention (52.6 % vs. 45.6 %, p = .35). These outcomes remained similar when assessed at three and six months. Within a year of buprenorphine-naloxone initiation, the study found no differences in the percentage of patients with hospitalizations (26.3 % vs. 38.3 %, p = .10), median number of hospitalizations (2 vs. 2), or proportion of days covered by a prescription >= 80 % (93.3 % vs. 92.0 %, p = .82).Conclusions: In this study, patients receiving once daily buprenorphine-naloxone had similar treatment outcomes to patients receiving split dosing. Further controlled studies are necessary to evaluate which patients are more likely to benefit from split dosing.