Safety and Efficacy of Cenobamate for the Treatment of Focal Seizures in Older Patients (P4-1.002)

Abstract

<h3>Objective:</h3> Safety (treatment-emergent adverse events [TEAEs] and efficacy with cenobamate were analyzed post-hoc for older adults aged 65–70 in a phase 3, open-label safety study. <h3>Background:</h3> Cenobamate is an antiseizure medication (ASM) approved in the US and EU for the treatment of uncontrolled focal seizures. <h3>Design/Methods:</h3> Adults 18–70 years old with uncontrolled focal seizures taking stable doses of 1–3 ASMs were enrolled. Concomitant ASM drug load changes from baseline to 1 year were measured (drug load defined as ratio of actual drug dose per day to the defined daily dose by the World Health Organization). <h3>Results:</h3> Of 1340 patients (mean age 39.7 years) who received ≥1 dose of cenobamate, 42 were aged 65–70 years (mean age 67.0 years). Median duration of exposure was 36.1 and 36.9 months for overall patients and older patients. 80%, 72%, and 68% of patients overall, and 76%, 71%, and 69% of older patients remaining on cenobamate at 1, 2, and 3 years, respectively. Discontinuation rates due to TEAEs were 13.6% (183/1340) in patients overall and 26.2% (11/42) in older patients. TEAEs reported in ≥20% of older patients were dizziness, somnolence, fall, fatigue, balance disorder, and upper respiratory tract infection. Efficacy (100% seizure reduction) was assessed in 240 patients with adequate seizure data available (n=18, ≥65 years). Rates of 100% seizure reduction within a 3-month interval during the maintenance phase increased over time for the overall population and older adults, reaching 52% and 77%, respectively by 24 months. Mean percent change in concomitant ASM drug load, not including cenobamate, was reduced in the overall population (29.44%) and older patients (31.18%). <h3>Conclusions:</h3> Results from this post-hoc analysis showed notable rates of efficacy in older patients when treated with adjunctive cenobamate. Further reductions in concomitant ASMs may be needed in older patients when starting cenobamate. See also abstract by Aboumatar et al. <b>Disclosure:</b> Dr. O’Dwyer has nothing to disclose. Mr. Stern has received personal compensation for serving as an employee of SK Life Science. Mr. Wade has nothing to disclose. Dr. Guggilam has received personal compensation for serving as an employee of SK Life Science, Inc. 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 $50,000-$99,999 for serving on a Speakers Bureau for SK Life Science. The institution of Dr. Rosenfeld has received research support from SK Life Science. The institution of Dr. Rosenfeld has received research support from UCB Pharma.