Cost-effectiveness analysis of intravenous levetiracetam versus intravenous phenytoin for early onset seizure prophylaxis after neurosurgery and traumatic brain injury

Abstract

Rashid Kazerooni1, Mark Bounthavong1,21Pharmacoeconomics/Formulary Management, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA; 2UCSD Skaggs School of Pharmacy and Pharmaceutical Sciences, San Diego, CA, USAObjective: There has been growing interest in newer anti-epileptic drugs (AEDs) for seizure prophylaxis in the intensive care setting because of safety and monitoring issues associated with conventional AEDs like phenytoin. This analysis assessed the cost-effectiveness of levetiracetam versus phenytoin for early onset seizure prophylaxis after neurosurgery and traumatic brain injury (TBI).Methods: A cost-effectiveness analysis was conducted from the US hospital perspective using a decision analysis model. Probabilities of the model were taken from three studies comparing levetiracetam and phenytoin in post neurosurgery or TBI patients. The outcome measure was successful seizure prophylaxis regimen (SSPR) within 7 days, which was defined as patients who did not seize or require discontinuation of the AED due to adverse drug reactions (ADRs). One-way sensitivity analyses and probabilistic sensitivity analysis were conducted to test robustness of the base-case results.Results: The total direct costs for seizure prophylaxis were $8,784.63 and$8,743.78 for levetiracetam and phenytoin, respectively. The cost-effectiveness ratio of levetiracetam was $10,044.91 per SSPR compared to$11,525.63 per SSPR with phenytoin. The effectiveness probability (patients with no seizures and no ADR requiring change in therapy) was higher in the levetiracetam group (87.5%) versus the phenytoin group (75.9%). The incremental cost effectiveness ratio for levetiracetam versus phenytoin was 360.82 per additional SSPR gained.Conclusions: Levetiracetam has the potential to be more cost-effective than phenytoin for early onset seizure prophylaxis after neurosurgery if the payer’s willingness-to-pay is greater than 360.82 per additional SSPR gained.Keywords: phenytoin, levetiracetam, seizure prophylaxis, cost-effectiveness, traumatic brain injury (TBI), and neurosurger