A rare disease is a condition that affects a small number of people. However, even though each rare disease affects few people, there are about 7,000 of these diseases. Altogether, they impact about 300 million people worldwide. Some rare diseases can be debilitating and life-threatening.
People with rare diseases commonly go years without proper diagnosis. Most often, this is because the diseases occur in so few people, and the symptoms can be confused with those of other conditions. Once diagnosed, people with rare diseases often have a hard time finding medical experts to treat them, or sufficient information about care for their conditions.
Around 80% of rare diseases are genetic, caused by a gene that doesn’t work properly. For most people with these diseases, the genetic mutation is there at birth, and the effect of the gene becomes more serious over time. At Pfizer, we’re conducting clinical trials in some rare diseases that fit this description. We invite you to explore our rare disease clinical trials below.
Explore our rare disease clinical trials

Select from the list below to view Pfizer clinical trials that are looking for participants. If you do not find what you are looking for, try using the search box below.