Exposure to rufinamide and risks of CNS adverse events in drug-resistant epilepsy: a meta-analysis of randomized, placebo-controlled trials.

Aim: Epilepsy is a complex disease necessitating continuous development of new therapeutic strategies to encounter drug-resistant cases. Among new adjuvant antiepileptic drugs, rufinamide is structurally distinct from other antiepileptic drugs. It is used to treat partial-onset seizures and seizures associated with Lennox-Gastaut syndrome (LGS) in adult and children. To date, there has been no attempt to evaluate systematically the risks of adverse events with rufinamide.

Methods: We performed a quantitative risk analysis of central nervous system (CNS) adverse events of rufinamide from all randomized, double-blind, add-on, placebo-controlled trials. The meta-analysis was undertaken with fixed effects models.

Results: Of the 886 publications reviewed, 99 papers were retrieved and five articles met the inclusion criteria. One thousand two hundred and fifty-two patients were included. Our study showed that exposure to rufinamide was associated with a significant increase in risk of somnolence [relative ratio (RR) 1.87; 95% confidence interval (CI) 1.33, 2.62; P = 0.0003], dizziness (RR 2.66; 95% CI 2.00, 3.55; P = 0.00001), fatigue (RR 2.14; 95% CI 1.57, 2.91; P = 0.01) and headache (RR 1.28; 95% CI 1.02, 1.59, P = 0.03). In addition, exposure to rufinamide was associated with higher treatment discontinuation rates as compared with placebo (RR 2.65; 95% CI 1.74, 4.03; P = 0.00001).

Conclusions: The risk of CNS adverse events appears to be increased in patients exposed to rufinamide as well as the treatment discontinuation rates. However, although statistical associations were significant, additional long term safety studies are required to confirm the clinical significance of these findings, as most reports described only mild and moderate adverse events.