An orphan disease is defined in the U.S. as:
o A rare disease that affects fewer than 200,000 people; or
o A common disease that has been ignored because it is less prominent in
the U.S., compared with developing nations.
The U.S. Orphan Drug Act of 1983 offers tax incentives on clinical
trials and seven years' market exclusivity on orphan drugs. Since the Act, more
than 200 orphan drugs have been approved by the FDA and are on the market.
According to the NIH, more than 6,000 so-called orphan diseases exist in the
U.S. With a mere 300 of these diseases being directly addressed in a therapeutic
manner, there is a large need to undergo development programs to counter orphan
diseases like SCD.