Intravenous lacosamide as replacement for oral lacosamide in patients with partial-onset seizures

Purpose: This multicenter, double-blind, double-dummy, randomized, inpatient trial evaluated the safety, tolerability, and pharmacokinetics of intravenous lacosamide as replacement for oral lacosamide in patients with partial-onset seizures. Methods: Patients were enrolled from an ongoing open-label extension trial of oral lacosamide and randomized (2:1) to either intravenous lacosamide and oral placebo or intravenous placebo and oral lacosamide. During the 2-day inpatient treatment period, patients received twice-daily doses of lacosamide equivalent to their current daily dose of oral lacosamide. The first 30 patients enrolled received infusions with 60-min durations and the next 30 received infusions with 30-min durations. Results: Of 60 patients randomized, 59 completed the trial. Treatment-emergent adverse events (AEs) were reported by 16 patients and included dizziness, headache, back pain, somnolence, and injection site pain. The tolerability profile of intravenous lacosamide was consistent with that of oral lacosamide. All AEs were considered mild or moderate in intensity, and no serious AEs or AEs leading to withdrawal were reported. Conclusions: Intravenous lacosamide, administered as 60- or 30-min twice-daily infusions, showed a similar safety and tolerability profile to oral lacosamide when used as replacement therapy. Results from this trial support further investigation of intravenous lacosamide at shorter infusion durations.