Effectiveness of eslicarbazepine acetate in dependency of baseline anticonvulsant therapy: Results from a German prospective multicenter clinical practice study

Abstract

Eslicarbazepine acetate (ESL) is a third-generation antiepileptic drug (AED) approved as monotherapy for partial-onset seizures in adults and as adjunctive therapy in patients aged above 6 years in the European Union (EU). The prospective observational Zebinix Effects in DEpendency of BAseline Conditions (ZEDEBAC) study aimed at investigating the effectiveness of ESL in clinical practice, with ESL being administered as monotherapy (mono group), as only add-on to a current monotherapy (1+ group), or as add-on to ≥2 baseline AEDs (≥2+ group). In total, 237 patients were included, 35 in the mono group, 114 in the 1+, and 88 in the ≥2+ group. Six-month retention rates were 93.9%, 78.0%, and 75.3% in the mono, 1+, and ≥2+ group. There were 90.5%, 77.6%, and 48.3% of patients in the mono, 1+, and ≥2+ groups who were responders (patients with a ≥50% reduction in seizure frequency at follow-up vs. baseline). Seizure freedom rates were 81.5%, 47.9%, and 23.4%, respectively. Adverse drug reactions (ADRs) occurred in 11.4% of patients of the mono, 19.3% of the 1+, and 28.4% of patients of the ≥2+ group. Hyponatremia was reported as ADR in 3.4% of all patients. Although baseline variables differed considerably, with most elderly patients with tumor-related and vascular etiologies in the mono group and most patients with refractory epilepsies with pronounced use of concomitant sodium channel blockers (SCBs) in the ≥2+ group, retention as a measure of real-life effectiveness turned out not to be substantially different and favorable in all groups.