Abstract Details

Title Efficacy of Cenobamate by Focal Seizure Subtypes: Post-hoc Analysis of a Phase 3, Multicenter, Open-Label Study

Topic Epilepsy/Clinical Neurophysiology (EEG)

Presentation(s) S13 - Epilepsy/Clinical Neurophysiology (EEG): Antiseizure Medications (2:00 PM-2:12 PM)

Poster/Presentation
Number 006

Background Cenobamate is an antiseizure medication (ASM) approved in the US for the treatment of adults with focal seizures.

Objective To report post-hoc retrospective efficacy data by focal seizure subtypes from 10 US study sites from a global, long-term, open-label phase 3 study.

Design/Methods Patients 18-70 years old with uncontrolled focal seizures taking stable doses of 1-3 ASMs were administered increasing daily doses of cenobamate (12.5, 25, 50, 100, 150, 200 mg/day) at 2-week intervals. Further increases to 400 mg/day by 50-mg/day increments every other week were allowed.

Results 240 patients with focal aware motor (FAM), focal impaired awareness (FIA), and focal to bilateral tonic-clonic (FBTC) seizure data were evaluated; 177 (73.8%) were continuing cenobamate at the last clinic visit on or after September 1, 2019 (mean duration 32.9 months). Twenty-seven (11.3%), 223 (92.9%), and 56 (23.3%) patients had FAM, FIA, and FBTC seizures, respectively (patients may have had ≥1 seizure subtype). Median baseline seizure frequencies/28 days were 10.5, 2.3, and 0.9 for FAM, FIA, and FBTC seizure subtypes. Reductions in median percent seizure frequency/28 days from baseline were observed during Months 1-3 (55.0%, 52.4%, and 94.1% for FAM, FIA, and FBTC). Greater reductions were observed during Months 3-5 (88.2%, 81.0%, and 100%) and during Months 24-27 (98.1%, 100%, and 100%). The percentage of patients achieving 100% seizure reduction in the FAM, FIA, and FBTC seizure subtypes was 22.2% (6/27), 21.5% (48/223), and 50% (28/56) during Months 1-3 and increased to 47.8% (11/23), 54.3% (88/162), and 90.5% (38/42) during Months 24-27, respectively. The most common treatment-emergent adverse events (≥20%) were fatigue, dizziness, and somnolence. No cases of DRESS were reported.

Conclusions Seizure reductions occurred in all focal seizure subtypes over time through Months 24-27, with the earliest onset in the FBTC group. These data support the long-term efficacy of cenobamate across focal seizure types.

Authors/Disclosures
William E. Rosenfeld, MD, FAAN (Comprehensive Epilepsy Care Center for Children and Adults) PRESENTER	The institution of Dr. Rosenfeld has received personal compensation in the range of $500,000-$999,999 for serving as a Consultant for SK Life Science. Dr. Rosenfeld has received personal compensation in the range of $100,000-$499,999 for serving on a Speakers Bureau for SK Life Science.
Louis Ferrari	Louis Ferrari has received personal compensation for serving as an employee of SK Life science.
Marc Kamin, MD	Dr. Kamin has received personal compensation for serving as an employee of SK LIFE SCIENCE INC.