New Research Highlights Need to Improve Lennox-Gastaut Syndrome Diagnosis, Non-Seizure Treatment Options
Lennox-Gastaut syndrome took an average of 12.3 months to be diagnosed after the first seizure, often leading to delays in treatment.
Konrad Werhahn
Data from a European real-world study revealed several significant challenges and unmet needs in Lennox-Gastaut syndrome (LGS), including delayed diagnosis time, poorer quality of life, and numerous concomitant morbidities. Overall, these findings underline the need for new treatments that target both drug-resistant seizures and the non-seizure symptoms of LGS.1
LGS, a type of developmental encephalopathy (DEE), is diagnosed based on appropriate clinical history (seizure types and intellectual impairment) in the presence of characteristic electroencephalogram (EEG) criteria. Data from the Adelphia LGS Disease Specific Programme, comprising 454 pediatric and adult patients with LGS across Europe, findings showed that it takes on average 12.3 months to receive a correct LGS diagnosis, following the first seizure at 4 years old (mean average age).
LGS is characterized by an electroclinical trend of generalized slow spike wave activity in the EEG, multiple types of epileptic seizures, and slow mental development. LGS can occur for many reasons; however, approximately 25% of cases have no identified cause. In the study, the data revealed that 71% of patients (324 of 454) experienced at least 1 concomitant comorbidity, with the most frequently reported including psychomotor or cognitive impairment, attention deficit hyperactivity disorder, sleep disorder, or insomnia.
"The impact of LGS goes beyond seizures and can include severe cognitive impairment, communication difficulties, psychiatric symptoms, behavioral challenges, and mobility problems, all of which constitute a major burden for patients and their caregivers/families," Konrad Werhahn, global medical affairs at UCB Pharma, said in a statement.1 "At UCB, we understand the need for a multidisciplinary, individualized approach to care which addresses each patient's medical, educational, psychological, and social needs throughout the course of their life."
Presented at the 15th European Epilepsy Congress, 19% and 28% of patients reportedly experienced severe or every severe physical and mental impairment, respectively, many of which persist with age. In addition, 47% of patients were reported to have at least somewhat poor quality of life. Furthermore, daytime seizures were considered the most troubling on quality of life, indicated by 39% of the cohort.
LGS accounts for approximately 2-5% of all childhood epilepsies, but it is responsible for roughly 10% of epilepsy cases occurring before the age of 5 years. Etiology of LGS can be divided into 2 subtypes: secondary or symptomatic LGS, and idiopathic or cryptogenic LGS. Secondary LGS can be caused by a number of factors, including tuberous sclerosis, infections/inflammation such as encephalitis, meningitis, injuries to the frontal lobes of the brain, birth injury/trauma, metabolic causes, and developmental brain malformations.
Identifying children with LGS at the earliest stages is critical to long-term development and access to available FDA-approved treatments, for which there are several. These include felbamate, lamotrigine, valproate, rufinamide, clobazam, topiramate, and cannabidiol, among others.2 Fenfluramine (Fintepla; UCB Pharma), an antiseizure medication, is considered the latest LGS treatment to reach market, becoming FDA-approved in 2022. It was originally approved as a therapy for those with Dravet syndrome in patients aged 2 years and older in 2020.3
Earlier this year, epilepsy expert Scott M. Perry, MD, sat down with NeurologyLive® to discuss the complexities with diagnosing LGS, and some of the downstream impacts failure to diagnose causes. Perry, head of neurosciences at the Jane and John Justin Neurosciences Center of Cook Children’s Medical Center, notes that LGS has become an increasingly difficult disorder to diagnose because of its various seizure types and presentation. In the clip below, he detailed the direct effects undiagnosed LGS has on treatments, connecting with patient advocacy organization, and future trials for drug development.
