Beyond seizures: proceedings of the ERN EpiCARE working group 18 on developmental and epileptic encephalopathies

Developmental and Epileptic Encephalopathies (DEEs) are rare, severe neurodevelopmental disorders characterized not only by refractory seizures but also by complex cognitive, behavioral, psychiatric, and psychosocial manifestations that profoundly affect long-term outcomes. Traditional seizure-centered endpoints capture only part of the disease burden and may fail to reflect priorities identified by patients and caregivers. This manuscript represents a conference proceedings paper developed within the ERN EpiCARE Working Group 18 ("Beyond Seizures"), integrating a structured narrative synthesis of current literature with thematic discussions held during the 2025 ERN EpiCARE Congress in Ålesund. Contributions from domain experts were harmonized through iterative review to identify shared priorities, unmet needs, and future directions in DEE care. The aim was not to develop formal consensus statements, but rather to identify shared priorities, unmet needs, and future directions in DEE care. Key domains addressed include neurodevelopmental trajectories, patient-centered outcomes, sleep disturbances, stigma, antiseizure medication effects beyond seizure control, neuropsychological rehabilitation, and transition to adult care. Across these areas, emerging evidence supports the integration of developmental, functional, and quality-of-life measures alongside seizure outcomes in both clinical practice and research. While advances in genetics and targeted therapies are reshaping the therapeutic landscape, substantial gaps remain in longitudinal data, standardized assessment strategies, and equitable access to multidisciplinary care. A coordinated, patient-centered, and lifespan-oriented approach is necessary to ensure that novel interventions meaningfully improve developmental and functional outcomes for individuals with DEEs and their families.