OBJECTIVES : Prior study has reported decrease in adherence to prescribed antiepileptic drug (AED) therapy with higher patient copay levels. The impact of patient copay on the likelihood of abandonment of prescribed AED has not been studied in pediatric patients with focal seizure (FS). This study assessed the association between patient copay and likelihood of AED treatment abandonment among pediatric patients with FS.

METHODS : Symphony Health’s Integrated Dataverse (IDV^®) open-source claims data for 04/01/15–06/30/18 were used to identify a sample of patients with a diagnosis of FS and ≥1 new approved AED pharmacy claim, <18 years old with ≥6 months of pharmacy data before and after. The index date was defined as the date of the first approved AED claim. Patient copay was defined as the expected patient out-of-pocket amount for the index AED claim in 2018 USD. Abandonment was defined as reversal of the index claim with no subsequent dispensation during the 6-month follow-up period. The association between copay level and odds of prescription abandonment was assessed using multivariable logistic regression.

RESULTS : Among the 9,529 patients meeting study criteria, 96% had an index claim for a generic AED. Mean (SD) expected copay for the index AED prescription was $14.55 ($73.6) [generic AEDs: $11.86 ($43.6); branded AEDs: $87.35 ($308.2)]. Overall abandonment rate for index AED prescriptions was 7.2% [generic AEDs: 6.4%; branded AEDs: 13.2%]. After adjustment, higher copay levels were associated with higher odds of prescribed AED abandonment, increasing from 1.47 (95% CI: 1.10–1.97) for $10–$15 copays to 2.21 (95% CI: 1.39–3.51) for $50–$100 copays. Patients with comorbid diagnoses of intellectual disability [OR: 1.83 (95% CI: 1.21-2.79)] and schizophrenia [OR: 8.59 (95% CI: 2.18-33.91)] had statistically significant higher odds of abandonment.

CONCLUSIONS : Higher patient copay levels are associated with higher odds of abandonment of prescribed AED treatment for pediatric patients diagnosed with FS.