The KCNT1-Related Epilepsy Study: Design and Methods of a Fully Decentralized Prospective Natural History Study in a...

KCNT1-related epilepsy is an ultra-rare pediatric-onset developmental and epileptic encephalopathy with a broad clinical phenotype ranging from, most commonly, severe infantile-onset epilepsy and global developmental delay to, less commonly, milder phenotypes including sleep-related seizures, autism spectrum disorder, and learning disability. We initiated the first-ever prospective natural history study to comprehensively clinically phenotype individuals affected by this disorder.

The primary aim of this study was to characterize seizures in individuals with KCNT1-related epilepsy. Secondary and exploratory aims included characterization of the full spectrum of disease symptoms, understanding caregiver burden, and collection of blood and urine samples for biomarker exploration. All study activities were conducted remotely (e.g., home-based assessments, telehealth visits).

Thirty-five participants (n = 20 male, 15 female) were enrolled in this study. The average age at the baseline visit was 76.0 months (s.d. = 75.5). This article presents the study design and methods and several challenges that arose in its implementation and discusses various solutions implemented in this medically complex population.

Future work will apply the lessons from this study in the planning and design of clinical trials for KCNT1-related epilepsy and possibly other developmental and epileptic encephalopathies.