Cenobamate in patients with highly refractory focal epilepsy: A retrospective real-world study

Purpose: To determine the effectiveness and safety outcomes of cenobamate in a cohort of patients with highly refractory focal epilepsy in routine clinical practice. Methods: Observational, retrospective, phase 4 study on subjects receiving cenobamate in three Spanish centers. The primary endpoint was the retention rate at the last follow-up. The main secondary endpoints were the 50%-responder and seizure-free rates at three months and the last follow-up. Other secondary endpoints were Global Clinical Impressions-Improvement (CGI-I) scores and treatment-emergent adverse events (TEAEs). Results: Fifty-one patients with highly refractory focal epilepsy with 24.7 years of disease evolution, ten previously tried ASM, and a 23.5% of previous epilepsy surgery were included. The retention rate at the last follow-up was 80.4%. The 50% responder rate in focal seizures at three months was 56.5% (median reduction per month 51%, 0-74.6; p < 0.0001) and in focal to bilateral tonic-clonic seizures was 63.6% (median reduction per month 89%, 0-100; p = 0.022). A total of 54.3% of subjects reported a reduction in the intensity of focal seizures, and 66% manifested clinically significant satisfaction. Cenobamate allowed a significant decrease in concomitant ASM, especially sodium channel blockers. TEAEs were reported in 43.1% of individuals, 85% of whom resolved or improved, with no new safety findings. Conclusion: In this analysis of patients with highly refractory focal epilepsy treated with cenobamate according to standard clinical practice, there was evidence of a high reduction in both seizure frequency and intensity, with a manageable safety profile.