Abstracts

Rationale: Approximately 30% of patients with epilepsy suffer from uncontrolled seizures. Perampanel is approved for adjunctive treatment of partial seizures with or without secondarily generalized seizures and for primary generalized tonic-clonic seizures in patients with epilepsy aged ≥12 years. The purpose of this study was to assess the impact of perampanel on health care resource utilization (HRU) among patients with epilepsy in the US. Methods: Using a large, nationally representative claims database, which captures over ½ of the annual US population that are commercially and publicly insured, from Symphony Health Solutions between 12/2012 and 11/2015, we identified 2,508 patients with ≥1 diagnosis of epilepsy, 12 years of age or older with at least 1 perampanel dispensing (the first Rx defined as the index date), and ≥180 days of continuous observation prior to and post the index date. All-cause and epilepsy-related HRU outcomes during the 180-day pre-perampanel period were compared to those of the post-period, using rate ratios that adjusted for varying observation periods across patients. Status epilepticus events occurring during a hospitalization were also identified. Rate ratios and their corresponding 95% confidence intervals of HRU outcomes were compared between the pre- and post-perampanel periods using conditional Poisson regression models. Results: The mean age of the perampanel cohort was 35.816.0 years old and 56.2% were female. On average, 459.8 (146.3 SD) days were observed in the post-index period. Post-perampanel periods were consistently associated with significantly lower rates of all-cause HRU than the pre-period across all HRU measures (Table 1). For the post- vs. pre-period, perampanel users had rates of 42.3 vs. 53.8 overall hospitalizations per 100 person-years (Rate Ratio (RR): 0.80; p < 0.0001) and 1,240.2 vs. 1,343.8 outpatient visits per 100 person-years (RR: 0.91; p < 0.0001). Epilepsy-related hospitalizations and outpatient visits were also significantly lower in the post- compared to the pre-period, with rates of 25.2 vs. 33.6 events per 100 person-years (RR: 0.76; p < 0.0001) and 327.0 vs. 389.0 events per 100 person-years (RR: 0.84; p < 0.0001), respectively. Additionally, a significantly lower rate of status epilepticus in the post-period (1.8 events per 100 person-years) was observed compared to the pre-period (4.4 events per 100 person-years; RR: 0.43; p < 0.0001). The monthly time trend of hospitalization rates showed an increasing trend leading to the initiation of perampanel, after which the hospitalization rates steadily decreased over the following months (Figure 1). Conclusions: The initiation of perampanel was associated with significant decreases in all-cause and epilepsy-related inpatient admissions and outpatient visits, and particularly substantial reductions in status epilepticus hospitalization events by more than 50%. Funding: This study was funded by Eisai, Inc., Woodcliff Lake, NJ, USA.