Over the past 4 decades since the Orphan Drug Act was passed in 1983, there have been tremendous advances in research, innovation, and regulatory policies that have spurred development of new treatments for rare diseases, but less than 5% of rare diseases have approved treatments on the market.1 More must be done to meet the needs of people living with rare diseases. The US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) play a critical role in ensuring that drugs to treat rare diseases and conditions are safe and effective.