An Online Survey of Caregivers of Patients with KCNQ2 Developmental and Epileptic Encephalopathy
Abstract number :
1.372
Submission category :
12. Genetics / 12A. Human Studies
Year :
2022
Submission ID :
2204802
Source :
www.aesnet.org
Presentation date :
12/3/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:26 AM
Authors :
Cynthia Harden, MD, FAES – Xenon Pharmaceuticals Inc.; Celene Grayson, PhD – Xenon Pharmaceuticals Inc.; Alix Helper, JD – Xenon Pharmaceuticals Inc.; Constanza Luzon Rosenblut, MD – Xenon Pharmaceuticals Inc.; Jim Johnson, . – KCNQ2 Cure Alliance; Caroline Loewy, . – KCNQ2 Cure Alliance; Scotty Sims, . – KCNQ2 Cure Alliance; John Millichap, PhD, FACMG – Northwestern University Feinberg School of Medicine; Noam Butterfield, PhD, PMP – Xenon Pharmaceuticals Inc.
Rationale: KCNQ2 developmental and epileptic encephalopathy (KCNQ2-DEE) is a rare, severe neurodevelopmental disorder caused by variants in the KCNQ2 gene, encoding the KV7.2 potassium channel. It is characterized by frequent daily refractory tonic seizures in the first days of life, severe developmental delays, cognitive impairment and motor disabilities. Seizure activity typically decreases with age with some patients becoming seizure free or experiencing a reduced seizure burden by 3 to 5 years of age. This online caregiver survey was conducted to better understand the seizure burden and treatment response in this patient population.
Methods: A 28-question online survey was developed to obtain de-identified data from caregivers of children with KCNQ2-DEE. The survey investigated demographics, seizure onset and frequency, prior and current use of anti-seizure medications (ASM), and caregiver perception of ASMs. All results were based on available responses and analyzed descriptively.
Results: Seventy-one caregivers completed the survey. The majority of patients included in the analyses (64%) were at least 4 years of age. Seizure onset was reported within the first 2 days of life for 91% of patients, and within the first 5 days of life for the remaining 9% of patients. At seizure onset, 58% of patients experienced more than 10 seizures per day. Most were initially treated with phenobarbital or levetiracetam. These were also the most common weaned treatments and rated by the caregivers as the worst mediations for seizure control. At the time of the survey, the current seizure frequency ranged from several per day to seizure freedom, with 47% reporting seizures over the past 6 months; more than half of these patients were at least 4 years of age. The current ASMs most frequently used were carbamazepine and oxcarbazepine, with these two ASMs cited as among the best for seizure control. 47% of patients were currently taking 2 or more ASMs, and in patients reporting seizures during the past month, more than half were taking 4 or more ASMs.
Conclusions: The significance of these caregiver survey results is that KCNQ2-DEE imposes a considerable seizure burden at disease onset, and that seizures persist in almost half of the patients, including patients 4 years of age and older. Moreover, caregivers described dissatisfaction with current treatment options. There is a significant unmet medical need that requires better treatments for KCNQ2-DEE.
Funding: Xenon Pharmaceuticals Inc.
Genetics