Pulmonary arterial hypertension (PAH) is a rare, chronic and life-threatening disease characterized by an abnormal and progressive increase in blood pressure in the small pulmonary arteries leading ultimately to right heart failure and death.
This increased blood pressure is caused by the narrowing of the small pulmonary arteries which are the blood vessels that carry blood from the right side of the heart through the lungs. PAH has an estimated prevalence in Europe of 15–60 cases per million.
There is currently no cure for PAH. Available therapies are agents that focus on improving the vasoconstriction-vasodilation balance without addressing the underlying cause of the disease. As a result, five-year median survival which is nearly 57% remains low despite treatment. Although the exact mechanisms leading to the onset and progression of PAH are still not yet fully understood, increasing scientific evidence points towards an inflammatory component underlying PAH.