Levetiracetam efficacy in PCDH19 Girls Clustering Epilepsy

Background: PCDH19 Girls clustering epilepsy (GCE) has a phenotypic spectrum that includes developmental and epileptic encephalopathy. PCDH19-GCE presents with clusters of seizures in the first years of life. Although patients typically outgrow their seizures, many are left with intellectual disability. Here we retrospectively assess the effect of levetiracetam in two independent cohorts of females with PCDH19-GCE. Methods: Cohort A was identified by searching our epilepsy genetics research database for girls with PCDH19-GCE who had trialled levetiracetam. Cohort B consisted of girls aged 2 years or older, including women, participating in an international online questionnaire. Information regarding seizure frequency and levetiracetam use was obtained by in-person patient interview and review of clinical records for cohort A, and by patient report for cohort B. Results: Cohort A consisted of 17 females, aged 3–37 years, who had a trial of levetiracetam at an average age of 10.7 years. 13/17 females became seizure free for >12 months; while 10/17 remained seizure free for >24 months. Cohort B comprised 62 females, aged 1.5–41 years. 26/62 became seizure free for >12 months, and 19/62 for >24 months on levetiracetam therapy. Discussion: Levetiracetam was effective in two cohorts of females with PCDH19-GCE where 42% and 76% of females became seizure free for >12 months, respectively. Levetiracetam is an effective therapy for females with PCDH19-GCE and should be considered early in the management of the highly refractory clusters of seizures that characterise this genetic disease.