The concept of orphan drugs was introduced to stimulate the development of therapies for rare diseases. Orphan drug designations can be granted by the Food and drug administration (FDA) if a drug is developed for a disease affecting less than 200,000 individuals in the US, and by the European Medical Agency (EMA) if it is developed for a disease affecting less than 1 in 2000 individuals. Incentives such as reduced development costs and extended market exclusivity aim to enhance their commercial attractiveness. However, challenges persist, including still high development costs, limited pre-approval data requiring extensive post-approval monitoring, and the financial strain high drug prices place on healthcare systems. As of this review, three antiseizure medications have received orphan drug approval in the European Union and four in the United States, collectively targeting four epilepsy syndromes, leaving a significant unmet need, particularly in developmental and epileptic encephalopathies. To address this, innovative trial designs are crucial for advancing orphan drug development.