America’s biopharmaceutical research companies are developing 452 new medicines for rare diseases, including genetic disorders, neurological conditions, infectious diseases and autoimmune disorders, according to a new report by the Pharmaceutical Research and Manufacturers of America (PhRMA).

Biopharmaceutical research is entering an era with a growing understanding of the human genome. Scientific advances have given researchers new tools to explore rare diseases, which are often more complex than common diseases. According to the FDA, in the last five years, one third of all new drug approvals were for rare diseases.

Although a rare disease is defined as one that affects fewer than 200,000 people in the U.S., there are approximately 7,000 rare diseases and collectively they affect nearly 30 million people, or one in 10 Americans.

“Biopharmaceutical scientists are better equipped than ever before to bring new treatments—and hope—to patients battling one of the nearly 7,000 rare diseases. In order to capitalize on this scientific promise, we need to ensure that we have a policy and regulatory environment that helps foster this vital work,” said John J. Castellani, PhRMA president and CEO.

The 452 medicines and vaccines in development for rare diseases, all in human clinical trials or under review by the FDA, include 105 for cancer, 85 for genetic disorders, 65 for blood cancers and 32 for neurological disorders.

Rare diseases provide opportunities to study human physiology and biomedical science from unique perspectives, leading to insight into more common disorders. Advances in science and technology, such as personalized medicine, are creating new opportunities to improve and expand both research and development into rare diseases.

The development of medicines for rare diseases also poses unique challenges, such as recruitment of volunteers for clinical trials since the patient population with a specific rare disease is typically very small, geographically dispersed and often children.