Pulmonary Arterial Hypertension
Pulmonary arterial hypertension (PAH) is an increase in blood pressure in the pulmonary artery, pulmonary vein, or pulmonary capillaries, together known as the lung vasculature, leading to shortness of breath, dizziness, fainting, and other symptoms, all of which are exacerbated by exertion. Depending on the cause, pulmonary arterial hypertension can be a severe disease with markedly decreased exercise tolerance and right-sided heart failure. The patient population suffering from pulmonary hypertension is estimated to be approximately 75 000 to 100 000 patients in the US and a similar number for Europe, with the diagnosed and treated number of patients being significantly lower.
Historically, PAH has been a very severe disease with three-year survival rates approximated to be 50% in patients with more progressed disease. Recent clinical studies have produced more than 90% two-year survival rates demonstrating the effectiveness of modern drugs. Indeed, current drugs, in many cases, can halt disease progression and/or improve clinical symptoms.
The combination of increased efforts in earlier diagnosis as well as improvements in drugs and drug combinations has led to a substantial increase in disease awareness. With the launch of the first oral drug seven years ago, the PAH market has grown from a few hundred patients to an estimated 60 000 patients on different drug therapies.
