To estimate the current incidence and prevalence of KCNQ2 epilepsy and to highlight the need for effective medications.

The natural history of KCNQ2 epilepsy is not well understood and published data estimating the epidemiologic burden is scarce. Variants in the KCNQ2 gene underlie a spectrum of rare early onset epilepsies with varying severity. KCNQ2 epilepsy includes self-limiting forms (BFNE) at the milder end of the spectrum, through to KCNQ2 developmental and epileptic encephalopathy (DEE), associated with developmental impairment and often refractory seizures. KCNQ2-DEE is recognized as a distinct genetic condition, and is an ideal target for treatment with a precision medicine approach, including Kv7 modulators.

Publications providing incidence estimates for KCNQ2 epilepsy were identified, and in addition, pathogenic variants in KCNQ2 accounted for a significant proportion of early onset genetic epilepsies. The current estimate for the birth incidence of KCNQ2 epilepsy is 1 per 17,000 live births (5.9/100,000) and ~1.2 per 100,000 for KCNQ2-DEE. Further modeling of the incidence and prevalence for KCNQ2 epilepsy is currently underway and will be presented.

Cases of KCNQ2 epilepsy are often undiagnosed or misdiagnosed, making it challenging to determine the true frequency in the population. Although there are uncertainties in some of the epidemiological parameters, the estimates of the incidence and prevalence of KCNQ2 epilepsy in this study provide a useful framework. Broader access to genetic testing will enable additional cases of KCNQ2 epilepsy to be identified and thus further refine epidemiological estimates and improve our understanding of the burden of KCNQ2 epilepsies.