In 2011, more than one third of new drug approvals in the United States were for orphan drugs. Once mainly pursued by small pharmaceutical or biotechnology companies, orphan drug development is now a focus of large pharmaceutical companies in search of therapies with “niche busting” potential.

While expedited regulatory approval and patent exclusivity for 7 years are the primary advantages for developing orphan drugs, several additional factors enhance opportunities. Patient advocacy groups for rare diseases can be valuable resources in funding clinical research and aiding patient enrollment.

In addition, orphan drugs can often be priced at a premium and marketed in a disease space with little competition. However, orphan drug development has unique challenges, and clinical development programs must be tailored to individual therapies and diseases. To maintain momentum with a development program, communication and collaboration between the sponsor, investigators, patient advocacy groups, and clinical research organizations is vital.

Orphan Drugs: Legislation and Gains

In the United States, there are approximately 7,000 rare diseases, defined as affecting fewer than 200,000 persons.3 Many rare diseases are chronic, progressive, disabling, and life-threatening. Examples include Huntington’s disease, amyotrophic lateral sclerosis (Lou Gehrig’s disease), Tourette syndrome, and muscular dystrophy. Among rare diseases, approximately 80% have a genetic origin, and half affect children.2

By definition, treatments for rare diseases target small populations of patients. Given their small market reach and resulting lack of interest from industry, drugs for rare diseases and conditions came to be known as “orphan drugs.”

Believing development of orphan drugs is in the public interest, in 1983 the United States Congress enacted legislation encouraging pharmaceutical manufacturers to develop drugs for rare diseases. The Orphan Drug Act lowered the procedural barriers for approval of drugs with orphan status and granted seven-year market exclusives.