Abstracts

RATIONALE: Oxcarbazepine (O) is an antiepileptic drug (AED) indicated for partial seizures as monotherapy or adjunctive therapy for adults and as adjunctive therapy for children ages 4-16. There are limited data on the economic implications of this therapy relative to older medications for partial seizures. The objective of this study was to explore resource use and costs among patients who were newly started on O or carbamazepine (C) therapy in a managed care setting.
METHODS: We employed a retrospective cohort design and administrative claims data to examine healthcare resource use and costs among patients prescribed O versus C. The study population included outpatients diagnosed with a seizure disorder who were newly started on O or C between Feb 1, 2000 (date of first availability of O) and Dec 31, 2000. The proportions of patients using seizure-related healthcare resource utilization and costs were assessed on a descriptive basis, in terms of the net change between the study cohorts from 6 months pre-index to 6 months post-index.
RESULTS: In total, 453 patients were eligible for inclusion; 414 in the C cohort and 39 in the O group. Patients averaged 36 years of age and 46% were male. Over 6 months, serum AED drug level assays increased 10.3% in the O group versus 20.5% in the C group, but the opposite was found for liver function tests (12.8% versus 7.5%, respectively). The increase in physician visits was smaller in the O group (2.5% vs. 6.7% for C). Moreover, while a decline was noted for ER visits and hospitalizations in both treatment cohorts, this decrease was greater in the O group (15.4% vs. 7.3%, and 7.7% vs. 0.2%, respectively). Correspondingly, mean medical costs per patient were $484 lower in the O cohort. This more than offset higher costs of therapy among O patients (mean: $261), resulting in an overall per-patient cost savings of $222.
CONCLUSIONS: This descriptive study suggests that in a managed care setting, relative to C, the use of O may be associated with lower healthcare utilization and costs among patients newly starting therapy. Whether the reduction in costs is due to better tolerability and/or improved seizure control cannot be directly assessed in a database study. However, the findings from this study suggest avenues for further outcomes research.[table1]
[Supported by: Novartis Pharmaceuticals Corp.]; (Disclosure: Salary - Sobin Chang is an employee of Novartis Pharmaceutics Corp., Grant - Luke Boulanger, Mark Friedman, Mellissa Yong, Peter Neumann, and Joseph Menzin received a research grant from Novartis Pharmaceuticals, Corp.)