Rare diseases are generally chronic, progressive, and often debilitating conditions that gradually impair an individual’s ability to carry out daily activities. The statistical definition of these diseases varies across countries.

In Iran, a rare disease is defined as a condition with a prevalence of fewer than 5 cases per 10,000 individuals. In the United States, rare diseases are defined as those affecting fewer than 200,000 people in the total population, while in Europe, the threshold is set at 1 in 2,000 individuals.

Currently, approximately 300 million people worldwide are living with rare diseases. In fact, it is estimated that 1 in every 20 individuals will encounter a form of rare disease at some point in their lives.