Orphan drug exclusivity is granted to drugs addressing rare 'orphan diseases' — those affecting fewer than 200,000 Americans.
The protection granted to orphan drugs is quite strong. The FDA is barred from approving any other biologic or small-molecule drug, generic/follow-on or otherwise, treating the same orphan disease for seven years.
This chart shows the companies which have received the most orphan drug exclusivities in the past five years.
The companies with the most orphan drug approvals are: