Fycompa found safe, effective for Dravet and other genetic epilepsies
Real-world analysis examined data from PERMIT Extension study
Fycompa (perampanel) was found to safely reduce seizure frequency among patients with genetic forms of epilepsy, including Dravet syndrome, in a recent analysis of real-world treatment data.
Findings from the analysis of pooled clinical practice data showed treatment responses among these genetic epilepsy patients were at least as good as those observed across a larger group of patients with epilepsy due to a variety of causes, or etiologies.
“This study’s findings indicate that PER is as effective, and possibly more effective, in treating individuals with a genetic epilepsy aetiology as it is in those with other aetiologies,” the researchers wrote.
The study, “Perampanel for the treatment of epilepsy with genetic aetiology: Real-world evidence from the PERMIT Extension study,” was published in Epilepsy Research. It was funded by Eisai, which marketed Fycompa until the medication was acquired by Catalyst Pharmaceuticals in 2o23.
Fycompa works to block certain signaling by a chemical messenger called glutamate that’s implicated in seizure onset. The oral therapy is approved in the U.S. for epilepsy patients ages 4 and older with partial seizures, and as an add-on therapy for those generalized tonic-clonic seizures, ages 12 and older.
In Europe, its cleared as an add-on for patients 4 and older with partial seizures, and for treating GTCS in people with idiopathic generalized epilepsy (IGE), a group of epilepsies presumed to be due to a genetic cause, but the exact origin hasn’t been discovered.
Genetic factors contribute to epilepsy in more than 50% of patients
It is believed genetic factors contribute to the onset of epilepsy for more than 50% of patients. This can include diseases like Dravet syndrome, where there is a known single genetic cause (i.e., mutations in the SCN1A gene), as well as other conditions where multiple, different genes contribute to an increased risk.
Existing data suggests Fycompa is effective and generally well tolerated when used to treat patients across a range of different genetic etiologies, including those with Dravet syndrome.
In the recent study, the researchers examined Fycompa’s real-world safety and efficacy among a subset of patients with epilepsy due to a presumed genetic cause who were included in the earlier PERMIT Extension study.
PERMIT Extension contains pooled clinical data from more than 6,800 epilepsy patients who were previously involved in two real-world studies of Fycompa. Among them 1,012 were believed to have epilepsy with a genetic etiology, most of whom (about 58%) had IGE.
Eight people, with a mean age of 23.8, had Dravet syndrome, and were using a mean of 2.3 other anti-seizure medications when starting on Fycompa (baseline).
Across all participants, the mean time on Fycompa over a one-year observation window was 10.8 months, with 65.9% of patients remaining on treatment after a year.
All five Dravet patients with evaluable data were considered treatment responders after a year of the therapy, meaning they experienced at least a 50% reduction in seizure frequency, with 20% seizure free since their last visit.
Five of seven patients were considered responders as of their last follow-up visit, with 28.6% being seizure free.
Across the larger group of patients with genetic epilepsy, around three-quarters of all participants (74.8%) were considered treatment responders after a year, and nearly half (48.9%) were entirely seizure free since their previous clinical visit.
For comparison, previous analyses across the entire PERMIT Extension population — including patients with a range of other nongenetic epilepsy causes — showed 59% of patients were treatment responders after a year and 24% were seizure free.
46.5% of patients experienced side effects from Fycompa
A little less than half of all patients in the recent analysis (46.5%) experienced side effects from Fycompa, with the medication’s tolerability consistent with its known safety profile. Five of eight children with Dravet experienced side effects, including irritability, fatigue, and sleepiness.
“Taken together with the findings from PERMIT Extension, current evidence therefore suggests that [Fycompa] is effective across a wide range of genetic aetiologies and demonstrates a consistent safety profile,” the researchers wrote.
They noted it is difficult to directly compare outcomes between specific subtypes of genetic epilepsy, given how small the groups were and that the number of other anti-seizure medications differed by epilepsy type.
“Given the generally small sample sizes of the specific genetic epilepsies that have been studied, it is currently not feasible to identify genetic factors and/or aetiologies that are predictive of the most favourable response to … treatment,” the team wrote.
The scientists also emphasized that given the study’s small size and its use of previously collected data, the “findings should only be considered as being descriptive and exploratory.”
“Further studies are required in order to determine whether [Fycompa’s] use may be particularly suitable for patients with specific genetic epilepsies,” the researchers concluded