The primary difference between a rare disease and an orphan disease, based on regulatory definitions in specific regions, lies in the prevalence thresholds used to define them. While both terms refer to conditions affecting a small portion of the population, the exact criteria vary.
Defining Rare vs. Orphan Diseases
Regulatory bodies in different parts of the world establish definitions for diseases based on how commonly they occur. These definitions are crucial for determining eligibility for specific incentives related to research and drug development.
The reference provided highlights the definitions used in the United States and the European Union, demonstrating this regional variation in terminology and criteria:
Key Distinctions Based on Prevalence
Here's a comparison based on the definitions given in the reference:
| Term | Region | Prevalence Definition |
|---|---|---|
| Rare Disease | United States | Affects fewer than 200,000 people. |
| Orphan Disease | European Union | Affects no more than 5 per 10,000 individuals. |
As shown in the table, the United States defines a rare disease based on an absolute number of affected individuals (fewer than 200,000), whereas the European Union defines an orphan disease based on a proportion of the population (no more than 5 per 10,000). These distinct prevalence criteria, applied in different regulatory contexts (US vs. EU), are the core difference presented.
Reference: 28-Feb-2024
