AAN 2022 | Cenobamate plasma concentrations in 50% and 100% responders

William E. Rosenfeld, MD, FAAN, The Comprehensive Epilepsy Care Center for Children and Adults, St Louis, MO, outlines a post-hoc analysis of cenobamate plasma concentrations in adult patients with uncontrolled focal seizures reaching 50% or 100% response rates. In total, 240 patients from the Phase III C021 safety study (NCT02535091) were enrolled, where cenobamate dose was incrementally increased up to 200mg/day. Cenobamate levels were assessed at the end of titration (first maintenance phase visit) and two weeks later. Of 177 patients who remained on cenobamate at data cut-off, the mean trough plasma concentration was 15.1 µg/ml. The mean concentration was 15.2 µg/mL in those who achieved a ≥50% responder rate during maintenance phase and 14.5 µg/ml in patients who were seizure-free for over 12 months. These data are consistent with observations from the Phase II studies (C013; NCT01397968 and C017; NCT0186611) with cenobamate 200 mg/day. This interview took place at the American Academy of Neurology 2022 Congress in Seattle, WA.