Evidence of Sex-Related Pharmacodynamic Differences in Photosensitive Epilepsy Treated with Valproate: Findings from a Retrospective, Observational, Single-Center, Within-Patient, Cohort Study

In our mixed-age population of pediatric, adolescent, and younger adults, significant sex differences were observed in the response of the PD EEG biomarkers, the PPR and SPR, to VPA for both primary outcomes. Males showed both a statistically greater reduction in EEG SPR and a statistically higher percent elimination of PPR on EEG with chronic VPA treatment compared with females. The percent of males having a clinically meaningful EEG SPR response to VPA, a secondary outcome, was almost two-fold greater for males compared with females. These findings emphasize the importance of considering sex in treatment planning and suggest that inherent biological differences may influence drug efficacy, advocating for further research to enhance personalized medical strategies.