In the United States, a rare disease is defined as a condition that affects fewer than 200,000 people, so it may be counterintuitive to realize that rare diseases cumulatively are not in fact rare. An astounding 7,000 rare diseases are known, and 30 more are being described each year. Eighty percent of these are genetic disorders, affecting 3 to 4 percent of all births. Although the number of individuals suffering from a single rare disease is small, the total number of individuals suffering from a rare disease is significant.
Prior to 1983, only a small number of rare diseases had approved therapies. Today, 302 rare diseases have approved therapies. In the last five years alone, 21 novel first-in-class treatments were approved for treating rare diseases. At present almost 600 companies are developing novel rare disease therapies, and there are now 729 gene therapies being studied in 1,855 clinical trials.
There are still significant challenges. In the diagnostic realm, the journey to diagnosis remains lengthy, complex and often ineffective, compounded by a lack of rare disease experts in any given geographic area. In the research arena, investigators confront many unknowns regarding a disease’s natural history or what endpoints and benefits should be considered meaningful to patients—and payers. There are a limited number of patients available to participate in often-competing clinical trials. Complicating all of this is that return on investment for companies sponsoring these trials is often uncertain and the reimbursement landscape for rare disease therapies remains volatile: both have important implications for patient access to effective treatments.
Nevertheless, numerous areas of progress and opportunity can be seen in the following examples: curative potential of gene therapies, growing networks of providers sharing information and referrals, increased data generation and sharing, and continued regulatory support and innovation with positive approval trends. Importantly, patients, their families and advocates have been driving forces at the center of many of these innovations, and their voices are being heard and growing stronger.