A randomized, open-label, multicenter comparative trial of levetiracetam and topiramate as adjunctive treatment for patients with focal epilepsy in Korea

Objective The objective of this trial was to compare the effectiveness of levetiracetam (LEV) and topiramate (TPM) as adjunctive treatment for patients with focal seizures in Korea. Methods In this Phase IV, open-label, multicenter trial (NCT01229735), adults were randomized to treatment with LEV (1000–3000 mg/day) or TPM (200–400 mg/day). Only patients achieving LEV ≥1000 mg/day or TPM ≥100 mg/day after a 4-week up-titration entered the 20-week dose-finding and subsequent 28-week maintenance periods. The primary outcome was the 52-week retention rate; others included safety and exploratory efficacy outcomes. Results Of 343 randomized patients (LEV 177; TPM 166), 211 (61.5%) completed the trial. In the full analysis set (FAS), retention rate was 59.1% with LEV vs 56.6% with TPM (p = 0.7007), while in the prespecified sensitivity analysis, based on data from patients who received drug doses in the recommended range (LEV 176; TPM 113), it was 59.1% with LEV vs 42.5% with TPM (p = 0.0086). In the FAS, median percent reduction in seizure frequency from baseline was 74.47% with LEV and 67.86% with TPM (p = 0.0665); ≥50% responder rate was 69.0% vs 64.8% (p = 0.4205), and the 6-month seizure-freedom rate was 35.8% vs 22.3% (p = 0.0061). In the sensitivity analysis, differences between groups were greater, favoring LEV. Incidences of treatment-emergent adverse events (TEAEs) were 70.6% with LEV vs 77.1% with TPM; most frequently somnolence (20.3%), dizziness (18.1%), and nasopharyngitis (13.6%) with LEV; and decreased appetite (15.7%), dizziness (14.5%), and headache (14.5%) with TPM. Discontinuations due to TEAEs were 7.9% with LEV and 12.7% with TPM. Conclusions In this open-label trial, the 52-week retention rate was not significantly different between LEV and TPM. However, LEV was associated with a substantially higher seizure freedom rate and a more favorable safety profile than TPM in this population of Korean patients with focal seizures.