atients with epilepsy in the UK will from this week have access to a novel treatment after Eisai launched Zebinix, a follow-on drug from the current gold standard therapy carbamazepine.
Doctors will now be able to prescribe Zebinix (eslicarbazepine acetate) as adjunctive therapy in adults with partial-onset seizures, with or without secondary generalisation, the firm said.
Epilepsy is a chronic neurological disease caused by abnormal discharges of neuronal activity causing seizures, which manifest as convulsions or muscle jerking, and affects around one in 100 people.
According to Eisai, treatment of partial-onset seizures, the most common type of epilepsy in which bursts of electrical activity are initially focused in specific areas of the brain, “presents a constant challenge – up to 40% of patients with partial-onset seizures do not achieve seizure control with current anti-epileptic drugs”.
In addition, it points out that current anti-epileptic agents frequently cause side effects such as dizziness, somnolence (sleepiness) and cognitive slowing, highlighting the urgent need for new anti-epileptic agents that are able to reduce seizures and have a better safety profile.
A Phase III clinical trial of Zebinix showed that the agent – technically a voltage gated sodium channel blocker – “demonstrated significant and sustained reductions in seizure frequency and significant increases in responder rates” Eisai said, as well as a more favourable safety profile as adverse events affected less than 10% of patients.
Once daily pill
This is because Zebinix has been developed from carbamazepine - the gold standard treatment since the 1950s – but with molecular changes to avoid the formation of a metabolite known to cause side effects. In addition, the drug can now be delivered in a one tablet once daily regimen, improving convenience and potentially boosting treatment compliance.
“Epilepsy continues to place a huge burden on individuals with the condition across the UK,” commented Mike Kerr, Professor of learning disabilities at Cardiff University. “Unfortunately despite advances in treatment and investigation many such patients continue to have seizures…[but]…The launch of eslicarbazepine acetate should offer a new choice for patients and clinicians in reducing the burden of epilepsy,” he added.