Efficacy and safety of eslicarbazepine acetate monotherapy for partial-onset seizures: Experience from a multicenter, observational study

- Eslicarbazepine is effective and well tolerated as monotherapy for patients with partial-onset epilepsy.
- Responder rates compared favorably to those responses described in III phase conversion to monotherapy trials.
- Eslicarbazepine was particularly efficacious in patients who suffered secondary generalized tonic-clonic seizures.
- Eslicarbazepine was generally well tolerated with a low rate of discontinuation caused by adverse events.

Eslicarbazepine acetate (ESL, Aptiom™) is a once-daily anticonvulsant, approved as adjunctive treatment of partial-onset seizures (POS). Historical-controlled trials investigating the use of ESL as monotherapy have demonstrated a favorable efficacy and tolerability profile in patients with POS. This prospective, non-interventional study recruited POS patients in 17 hospitals in Spain. After a 3-month baseline period, ESL therapy was initiated as 400 mg QD and up-titrated to an optimal maintenance dose based on clinical response and tolerance. The incidence of seizures was assessed via seizure calendars and the nature and severity of adverse events (AEs) were also recorded. A total of 117 patients (aged 9-87 years) enrolled in the study and were treated with ESL at either 400 mg/day (3.4% patients), 800 mg/day (61% patients), 1200 mg/day (27.1% patients) or 1600 mg/day (8.5% patients). At 3 months, 82.0% (n = 72) of patients achieved a ≥ 50% reduction in seizure frequency, compared to 79.7% (n = 67) of patients at 6 months and 83.0% (n = 49) at 12 months. Patients who suffered secondary generalized tonic-clonic (SGTC) seizures had seizure-free rates of 71% (n = 27), 69.6% (n = 29), and 72.7% (n = 16) at 3, 6, and 12 months, respectively. Overall, 18 patients (15.3%) reported AEs of instability and dizziness (n = 9), somnolence (n = 3), mild hyponatremia (n = 3), headache (n = 1), hypertriglyceridemia (n = 1), and allergic reaction (n = 1), which caused ESL discontinuation of ESL treatment. ESL is effective and well tolerated as monotherapy for patients with POS, which supports previous findings. Early use is supported by its frequent use as monotherapy in this study and lack of severe side effects.