European Commission grants Marketing Authorisation for Zebinix® (eslicarbazepine acetate) as once-daily monotherapy in adults with newly diagnosed partial-onset epilepsy
Bial and Eisai announced on 23rd May that the European Medicines Agency (EMA) has approved Zebinix® (eslicarbazepine acetate) for use as a once-daily monotherapy to treat adults with newly-diagnosed partial-onset epilepsy. Zebinix® is already indicated in Europe as adjunctive therapy in adults, adolescents and children aged above 6 years, with partial-onset seizures with or without secondary generalisation.1
This marketing authorisation is based on results from a Phase III, randomised, double-blind, active-controlled, non-inferiority study (Study 311) which compared once-daily eslicarbazepine acetate as monotherapy to twice-daily, controlled-release carbamazepine in newly diagnosed adults with partial-onset seizures. The primary endpoint was the proportion of patients seizure-free for the entire 26-week evaluation period.2 The data show that 71.1% (n=276/388) of patients for eslicarbazepine acetate and 75.6% (n=300/397) of patients for controlled-release carbamazepine were seizure-free for six months or more, at the last evaluated dose (average risk difference -4.28%; 95% CI -10.3, 1.74%). The one-year seizure-freedom rate at the last evaluated dose was 64.7% (n=251/388) on eslicarbazepine acetate and 70.3% (n=279/397) on controlled-release carbamazepine (average risk difference: -5.46%; 95% CI: -11.88, 0.97%).2
“Epilepsy is a chronic disorder of the brain and one of the most common neurological conditions worldwide,” said Eugen Trinka, Professor and Chair of Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria. “This approval brings the promise of a new monotherapy option for over half of patients with epilepsy who experience partial-onset seizures.”
Eslicarbazepine acetate has an innovative mode of action that is different from other sodium channel blockers.1,3 It selectively targets the slow inactivated state of the sodium ion channel (which has been implicated in the pathogenesis of epilepsy), preventing its return to the active state,3 and thereby reduces repetitive neuronal firing, based on animal data.3 The recommended starting dose is 400 mg once daily which should be increased to 800 mg once daily after one or two weeks. Based on individual response, the dose may be increased to 1,200 mg once daily. Some patients on a monotherapy regiment may benefit from a dose of 1,600 mg once daily.1
“We are pleased that adults with partial-onset epilepsy across Europe are now able to benefit from a once-daily monotherapy option that is simple to use, which may optimise their adherence,” comments António Portela, CEO of Bial, Porto, Portugal. “Bial has an ongoing commitment to all people living with epilepsy and we look forward to continuing to work with the epilepsy community to bring this new indication to patients.”
“This decision for eslicarbazepine acetate by the European Commission reinforces Eisai’s commitment to researching and developing neurological treatment options that have the potential to help people manage epilepsy more effectively. This milestone means that newly-diagnosed adult patients in Europe who experience partial-onset epilepsy will now have a broader range of treatment options available,” comments Neil West, Vice President EMEA, Global Neurology Business Unit at Eisai.
A safety analysis of the Phase III study showed that the tolerability profile of eslicarbazepine acetate was similar to that of twice-daily controlled-release carbamazepine.4 The side effects of eslicarbazepine acetate were mostly of mild intensity, and consistent with the known safety profile.
Incidence rates of treatment-emergent adverse events (TEAEs) were similar but slightly higher in patients receiving controlled-release carbamazepine (77.7%) (n=320/412) versus eslicarbazepine acetate (75.3%) (n=302/401). Possibly-related TEAEs were also slightly higher at 49.5% (n=204/412) for controlled-release carbamazepine compared with 41.1% (n=165/401) for eslicarbazepine acetate, for serious possibly-related TEAEs (2.7% vs 2.0%) (n=11/412 vs n=8/401), and for TEAEs leading to withdrawal (18.0% vs 13.5%) (n=74/412 vs n=54/401). The most frequently reported possibly-related TEAEs for eslicarbazepine acetate were, in order of most frequent, dizziness, headache, somnolence, fatigue and nausea.4
References
1 Zebinix® (eslicarbazepine acetate) Summary of Product Characteristics. Available at: http://www.medicines.org.uk/emc/medicine/22376 Accessed May 2017.
2 Ben-Menachem E, et al. Efficacy of eslicarbazepine acetate versus controlled-release carbamazepine as monotherapy in patients with newly diagnosed partial-onset seizures; European Congress on Epileptology 2016: Abstract #0002
3 Hebeisen S, et al. Eslicarbazepine and the enhancement of slow inactivation of voltage-gated sodium channels: a comparison with carbamazepine, oxcarbazepine and lacosamide. Neuropharmacology 2015; 89:122-35
4 Kowacs P, et al. Safety and tolerability of eslicarbazepine acetate as monotherapy in patients with newly diagnosed partial-onset seizures. Presented at EAN 2016; abstract #P32045
5 Elger C, et al. Eslicarbazepine acetate: A double-blind, add-on, placebo-controlled exploratory trial in adult patients with partial-onset seizures. Epilepsia 2007; 48:497-504
6 Elger C, et al. Efficacy and safety of eslicarbazepine acetate as adjunctive treatment in adults with refractory partial-onset seizures: A randomised, double-blind, placebo-controlled, parallel-group phase III study. Epilepsia. 2009;50:454-63
7 Ben-Menachem E, et al. Eslicarbazepine acetate as adjunctive therapy in adult patients with partial epilepsy. Epilepsy Res. 2010;89(2-3):278-85
8 Gil-Nagel A, et al. Efficacy and safety of 800 and 1200 mg eslicarbazepine acetate as adjunctive treatment in adults with refractory partial-onset seizures. Acta Neurol Scand. 2009; 120:281-87
9 Epilepsy in the WHO European Region: Fostering Epilepsy Care in Europe. Available at: http://www.ibe-epilepsy.org/downloads/EURO%20Report%20160510.pdf Accessed March 2017
