There are 6000 rare diseases that exist in the United States, defined by FDA as diseases that affect fewer than 200,000 people.
According to this definition, approximately 30 million Americans have a rare disease; however, only about 200 of these approximately
6000 diseases have targeted products approved for their treatment. Pharmaceutical companies that develop drugs targeting
these small populations, known as orphan drugs, have been able to successfully develop drugs for orphan disorders with the
incentives offered by the Orphan Drug Act. These incentives have allowed not only for some companies (usually small- and
medium-sized companies) to build highly successful businesses by targeting orphan disorders, but are also now attracting the
interest of larger pharmaceutical companies that are often entering orphan-drug development for the first time.
The US Orphan Drug Act was adopted 1983 to create financial incentives, including grants, for developers of orphan-drug treatments.
Since the Act was passed, more than 360 drugs and biological products have received orphan-designated market approval. The
2007 FDA Amendments Act gave FDA the authority to award priority review vouchers to sponsors of certain neglected-disease
treatments that receive marketing approval as well. Neglected diseases include tuberculosis, leprosy, and malaria, and are
defined as affecting more than one billion people in the developing world. In addition, companies can now file a common application
for orphan-product designation to FDA and the European Medicines Agency.
In February 2010, the agency added a new Associate Director of Rare Diseases to the Center for Drug Evaluation and Research
(CDER), Anne Pariser, to complement the work of the existing Office of Orphan Products Development (OOPD). The office is
working to support rare-disease review and regulation within the Office of New Drugs, part of CDER.
OOPD has since launched a database for drug developers called the Rare Disease Repurposing Database (RDRD). This past fall,
FDA cosponsored the first annual Rare Disease Investigator Training Course, and is collaborating with the National Institutes
of Health to form work groups to enhance regulatory and translational science development for rare-disease research and related
Although these efforts are moving in the right direction to help populations afflicted with rare or neglected diseases worldwide,
FDA and regulators face great challenges when it comes to improving health outcomes for patients overall. According to Drs.
Pariser and Tim Coté of OOPD, "Developing treatments for rare disease is a challenging new area of drug development and works
best when all stakeholders—industry, patient advocates, academia, and governmental agencies—are involved in the process from
drug discovery through to clinical investigations and commercial marketing." Looking ahead, Pariser and Coté add that, "enhanced
collaboration between rare-disease stakeholders, especially through the advancement of rare-disease research and regulatory
science, is an area FDA will continue to focus on as we work to further support the development of treatments for rare disease."
As a result of the 2010 US Appropriations Act, FDA established two internal committees to examine rare and neglected diseases.
The committees' report to Congress is due to be published this month, March 2011.