Rare Diseases Epidemiology: Update and Overview

Tran T. Le

Over 30 years ago, the United States (US) Congress passed the Orphan Drug Act (ODA) to encourage the development of products for rare diseases or conditions ("orphan products"). The Act provided incentives to sponsors for developing products with orphan designation and established a grant program to fund studies of orphan products. Since its enactment in 1983, the ODA has been credited for bringing more than 590 orphan drugs to the market, inspiring the implementation of orphan legislation globally, and enabling the creation of other programs that extend existing knowledge of the natural history of rare diseases and stimulate the development of medical devices for children and patients with rare diseases. This chapter provides a brief overview of the main features and successes of 5 of the orphan incentive programs administered by the US Food and Drug Administration (FDA): the Orphan Drug Designation Program, the Humanitarian Use Device (HUD) Designation Program, the Orphan Products Clinical Trials Grants Program, the Pediatric Device Consortia (PDC) Grant Program, and the Orphan Products Natural History Grants Program.