Abstracts

Rationale: Antiepileptic drugs (AEDs) are a common treatment for patients diagnosed with epilepsy. Though there are currently more than 20 generic and branded AEDs on the market, some patients remain refractory to medication treatment and continue to have seizures. While most AEDs act by attenuating calcium and/or sodium channels or enhancing inhibitory signals, perampanel uniquely inhibits the excitatory AMPA glutamate receptor. Clinical trial data has shown it to be efficacious in the treatment of epilepsy, and it is approved for partial onset seizures (POS) in pediatric and adult patients (ages 4 to adult) and as adjunct in primary generalized tonic clonic (PGTC) seizures for patients >=12 years old.The purpose of this model was to estimate the one-year budget impact of increased utilization of perampanel consistent with its approved indication in a US commercial health plan from a payer perspective.  Methods: A Microsoft Excel-based model was developed to assess the costs to commercial payers treating children and adults with perampanel. Using a hypothetical plan of 1-million members, the model compared a baseline year with a small perampanel market share (0.7%) versus a comparator year with 2.5% perampanel market share (an approximate 250% increase). Model inputs, including eligible population, market share, drug costs, and healthcare utilization rates and costs, were based on pricing guides and analyses of commercial claims data. Increased perampanel market share was shifted from alternative branded competitors (i.e., brivaracetam, eslicarbazepine, and lacosamide). Model outcomes included total annual plan costs, per-member per-month (PMPM) costs, and cost per treated patient (PTP). Parameter uncertainty was examined with a one-way sensitivity analysis. All costs were reported in 2018 $US.  Results: Among an initial plan of 1 million-members, we estimated that 3,197 patients aged 4 to adult would be treated with an AED. Using the change in market share described above and perampanel's daily acquisition cost at $29.90 (with competitors ranging from $29.94 to $35.67), the results showed an incremental annual plan cost savings of -$155K or -$0.01 PMPM. Annual cost PTP for perampanel was $18,212, compared with PTP costs of $20,241, $17,090 and $21,467 for branded competitors. Results were robust to one-way sensitivity analyses. Conclusions: The results showed that increasing the utilization of perampanel consistent with label in a population of pediatric and adult patients with POS and PGTC can potentially reduce pharmacy and overall health care costs to a health plan. This saving occurs in an environment with increased flexibility and options for treating patients with refractory epilepsy. These findings can be used to inform formulary decision making.  Funding: Financial support for this study was provided by Eisai Inc.