Study of Bosentan in the Treatment of Stable Severe Chronic Obstructive Pulmonary Disease Patients

Present treatment for chronic obstructive pulmonary disease (COPD) has a certain role in reducing COPD exacerbation and hospitalization, improving the life quality, and postponing the lung function decline. But for some patients with severe COPD, current treatment only partially alleviates the symptoms and has little role in the lung function decline. In this randomized, multicenter study, the investigators evaluate the safety and efficacy of bosentan in the treatment of grade Ⅲ or Ⅳ COPD patients with pulmonary hypertension detected by echocardiography. The primary endpoint is the frequency of COPD exacerbation, and the secondary endpoint includes changes of lung function, 6-min-walk distance (6-MWD), SGRQ score and mMRC/CAT score.