Cenobamate Reduces Seizure Frequency Regardless of Concomitant AEDs

Jeong Woo Cho, PhD

Data from a post-hoc analysis of the YKP3089C017 (C017; NCT01866111) study demonstrated a reduction in seizure frequency with treatment with cenobamate (Xcopri; SK Life Science) in patients with epilepsy, regardless of their baseline number of antiepileptic drugs (AEDs).

The data had been scheduled to be presented at the American Academy of Neurology (AAN) 2020 Annual Meeting.

The double-blind, placebo-controlled, dose-response study evaluated patients on stable doses of 1 to 3 AEDs who were randomized to placebo or cenobamate 100, 200, or 400 mg/day. Median reduction in seizure frequency for patients who were taking 1 baseline AED (n = 64) was 24.1% for the placebo group and 44.7%, 57.6%, and 86.0% for the cenobamate 100-, 200-, and 400-mg/day groups, respectively.

Compared with those who were on 2 AEDs (n = 156), the median percent reductions were 33.3% for placebo and 41.4%, 57.9%, and 57.0% for the 100-, 200-, and 400-mg/day doses. Additionally, those who were taking 3 AEDs (n = 177) with treatment showed a median percent reduction of 26.4% in the placebo group and 41.5%, 49.3%, and 67.4% reduction for the cenobamate groups (100, 200, 400 mg/day, respectively).

The post-hoc assessment, conducted by Jeong Woo Cho, PhD, President and CEO of SK Biopharmaceuticals and SK Life Science and colleagues aimed to evaluate the effects of baseline features, including number of concomitant AEDs, seizure frequency, and epilepsy duration on the reduction of focal seizure frequency during the maintenance phase of study C017.

Patients included in C017 were 18 to 70 years old with uncontrolled focal seizures who also had >8 focal seizures during the 8-week baseline period. Each patient underwent a 6-week titration phase and a 12-week maintenance phase.

Rosenfeld and colleagues concluded that the results of C017 showed that cenobamate 100, 200, and 400 mg were effective for the treatment of focal seizures.

Post-hoc results suggest that even when assessed by median baseline seizure frequency per 28 days (9.5), a reduction in median seizure frequency was observed in 66.5% of patients on cenobamate 200 mg with baseline seizure frequency above the median (<9.5)—the greatest reduction of all dose groups. Patients with baseline seizure frequency >9.5 had the most success with cenobamate 400 mg, with 70.7% of patients seeing their highest reduction.

Rosenfeld and colleagues observed similar trends when assessed by median duration of epilepsy at baseline (<23 years/>23 years). Additionally, regardless of baseline seizure frequency or disease duration, responder rates (>50% seizure reduction) were numerically higher in each cenobamate group compared with placebo.

The FDA originally approved cenobamate for the treatment of partial-onset seizures in adults in November 2019. Trials assessing the efficacy and safety of cenobamate in over 1900 patients showed the drug’s ability to significantly reduce partial-onset seizure frequency, with up to 20% of patients achieving seizure-free status during the maintenance phases.

In early March, SK Life Science also announced that cenobamate had been designated as a Schedule V medicine by the DEA, the lowest designation for abuse from the agency. With the final step of the regulatory process complete, the company anticipates launching cenobamate in the second quarter of 2020.

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REFERENCE

Rosenfeld WE, Nisman A, Cho JW, Ferrari L. Efficacy of adjunctive cenobamate in patients with uncontrolled focal seizures based on number of concomitant antiepileptic drugs, seizure frequency, and epilepsy duration at baseline. Neurology. 2020;94(15 Suppl): 1025.