To investigate the efficacy and safety of adjunctive cenobamate for treatment of uncontrolled focal seizures.
We performed a systematic search of Web of Science, MEDLINE (Ovid and PubMed), Cochrane Library, EMBASE and Google Scholar to identify eligible studies. We included randomized placebo-controlled trials (RCTs) for uncontrolled focal seizures. We calculated the risk ratio (RR) of ≥50%, ≥75% and 100% reduction in seizure frequency from baseline, as well as dropout and serious adverse events related to treatment. Quality of included trials was assessed using the Cochrane Collaboration’s tool.
Two RCTs with a total of 658 patients were included. A significantly larger proportion of patients allocated to cenobamate achieved 50% seizure reduction (RR 2.06, 95% CI 1.70–2.51, p < 0.001) as compared to placebo, subgroup analysis demonstrated that the most effective dose was at 400 mg (RR 2.28, 95% CI 1.57–3.32, p < 0.001). Patients achieving seizure-freedom during the treatment period were 14.9% with cenobamate and 4.5% with placebo (RR 5.32, 95% CI 2.94–9.62, p < 0.001). Dropouts (RR 1.40, 95% CI 1.01–1.94, p = 0.05) and incidence of serious adverse events (RR 1.48, 95% CI 0.93–2.33, p = 0.1) were not significantly higher in patients receiving cenobamate. However, subgroup analyses based on doses suggested that patients exposed to 400 mg cenobamate were more likely to dropout than placebo (RR 2.09, 95% CI 1.17– 3.71, p = 0.012).
Cenobamate demonstrated favourable efficacy for treatment of uncontrolled focal seizures and showed a dose-related fashion. Cenobamate could be well tolerated, the most common adverse events associated with cenobamate were dizziness, somnolence, fatigue, headache and nausea. Nevertheless, majority of them were mild to moderate in severity.