Real-World Comparison of Olanzapine/Samidorphan vs Olanzapine: An Assessment of Treatment Patterns and Acute Care Events Among Patients With Bipolar I Disorder
INTRODUCTION: Weight gain associated with antipsychotic treatment may contribute to nonadherence and subsequent increased risk of hospitalization. Combined olanzapine/samidorphan (OLZ/SAM) provides the antipsychotic efficacy of olanzapine while mitigating olanzapine-associated weight gain in patients with bipolar I disorder (BD-I). This analysis compared treatment patterns and acute care events in patients with BD-I initiating OLZ/SAM versus olanzapine.
METHODS: This claims analysis used Komodo Healthcare Map data (10/18/2020-12/31/2023). Adults with BD-I enrolled in Medicaid with ≥1 OLZ/SAM or olanzapine claim were eligible. Patients were propensity score matched 1:1 on demographic/clinical variables. Treatment patterns (adherence, persistence, discontinuation), inpatient (IP) admissions, emergency department (ED) visits, numbers of days hospitalized per patient, and times to first IP admission were compared in a 12-month follow-up period.
RESULTS: After matching, 1008 patients with BD-I (OLZ/SAM, n=504; olanzapine, n=504) were included. OLZ/SAM was associated with significantly (P< 0.001) higher adherence, longer persistence, and lower discontinuation rates over 12 months versus olanzapine. OLZ/SAM was associated with significantly (P< 0.05) lower likelihood of ≥1 all-cause, mental health-related, or BD-I-related IP admission (odds ratio [OR] range, 0.52-0.58) or ED visit (OR range, 0.62-0.74). Across all-cause, mental health-related, and BD-I-related events, mean times to first IP admission were significantly (P< 0.05) longer (range, 28-35 days) and mean numbers of days hospitalized per patient were significantly (P< 0.001) lower (range, –3.2 to –4.5 days) in patients initiating OLZ/SAM.
CONCLUSIONS: OLZ/SAM treatment offers meaningful real-world effectiveness benefits over olanzapine alone, as observed by favorable treatment patterns and lower likelihood of relapse and related acute care events.
