Observational study of intravenous lacosamide in patients with convulsive versus non-convulsive status epilepticus

Status epilepticus (SE) is an important emergency situation associated with high morbidity and mortality. The goal of pharmacological therapy-rapid seizure termination-is only achieved in just over half of patients with first-line anti-epileptic drug (AED) therapy and many patients require second and higher lines of AEDs to achieve seizure termination; therefore, there is a clear need for more effective treatment options. Lacosamide is a relatively new AED and the intravenous formulation has shown promise for treatment of SE. The aim of the current study was to compare electroencephalographic (EEG) response and seizure termination with intravenous lacosamide (±other AEDs) in patients with convulsive versus non-convulsive SE, in a Spanish intensive care setting.

In this prospective, observational study, patients with convulsive or non-convulsive SE who received intravenous lacosamide 400 mg/day for 8 days were compared in terms of EEG response and seizure termination. Adverse events were not specifically assessed.

Fifty-three patients (69.8 % male; mean age 55.2 years) were treated with lacosamide (mean dose 390.6 mg) as first- (20.8 %), second- (34 %), third (22.6 %) or fourth-line (22.6 %) treatment for convulsive (n = 23, 43.4 %) or non-convulsive (n = 30, 56.6 %) SE. The majority of patients (73.6 %) had a comorbid condition, predominantly hypertension (35.8 %), and most (79.2 %) received at least one concomitant AED, including midazolam (54.7 %), valproic acid (52.8 %), and levetiracetam (30.2 %). Patient characteristics and treatment received did not differ significantly between the convulsive and non-convulsive SE groups. EEG recordings following lacosamide treatment demonstrated the elimination of paroxysmal activity (disappearance and/or attenuation of epileptiform activity in >60 % of recording time) in 56.6 % of patients; 69.6 % of convulsive and 46.7 % of non-convulsive SE groups. Among all patients, 90.6 % showed some EEG improvement (disappearance of epileptiform activity in <30 % total recording time or disappearance and/or attenuation of epileptiform activity in 30-60 % total recording time); and there was no significant between-group difference for achievement of seizure termination (90.0 vs. 91.3 % for non-convulsive vs. convulsive SE).

Intravenous lacosamide (±other AEDs) was similarly effective in patients with convulsive or non-convulsive SE. Further investigation into the use of lacosamide in the treatment of SE is warranted.