(#42) Real-World Treatment Patterns of Patients With Schizophrenia Using Oral Olanzapine and the Associated Impact of Non-adherence on Healthcare Resource Utilization

Abstract: Non-adherence to oral antipsychotics is a barrier to optimal outcomes for patients with schizophrenia. This study aimed to identify treatment patterns and the impact of treatment non-adherence on healthcare resource utilization (HCRU) for patients receiving oral olanzapine. This retrospective study using the US MarketScan Medicaid Claims database included adult patients with schizophrenia (?1 inpatient/?2 outpatient diagnoses;ICD-10:F20) who initiated oral olanzapine (2019ñ2021). Patients had ?1 additional oral olanzapine claim within 90 days. Treatment patterns and HCRU were assessed for adherent (proportion of days covered [PDC]?0.8) and non-adherent (PDC 0.8) cohorts over 1 year. For HCRU, cohorts were matched 1:1 using a propensity score for baseline covariates. Overall, 3860 patients were included (mean age 39.7 years, 60.4% male); 775 (20.1%) were adherent to oral olanzapine. Adherent patients were more persistent and had fewer switches versus non-adherent patients (659/775[85.0%] vs 254/3085[8.2%] and 62/775[8.0%] vs 1824/3085[59.1%], respectively). During the first-year post-oral olanzapine initiation, matched adherent versus non-adherent patients had fewer mean all-cause hospitalizations (0.49 vs 1.13), fewer mean ER visits (1.72 vs 3.01) (both per patient per year [PPPY] and p 0.0001) and numerically lower mean total costs ($27,995.13 vs $31,213.95). Similarly, schizophrenia-related mean HCRU was lower for adherent versus non-adherent patients at 1 year (hospitalizations: 0.22 vs 0.55 PPPY, p 0.0001; ER visits: 0.4 vs 0.8 PPPY, p 0.0001); schizophrenia-related total costs were similar and non-significant ($9191.80 and $9592.82, respectively). These results demonstrate the prevalence and burden of non-adherence to oral olanzapine, suggesting a need for a viable olanzapine long-acting injectable to improve adherence rates.Short Description: This real-world study aimed to identify treatment patterns and healthcare resource utilization (HCRU) of oral olanzapine in patients with schizophrenia. Only 20.1% (775/3860) of patients were adherent to oral olanzapine over 1 year. Non-adherence was associated with increased all-cause and schizophrenia-related HCRU, primarily due to hospitalizations and ER visits. These results demonstrate the prevalence and burden of non-adherence to oral olanzapine, suggesting a need for a viable olanzapine long-acting injectable to improve adherence rates.Name of Sponsoring Organization(s): Teva Branded Pharmaceutical Products R&D LLC