Bufei Yishen Granule for Reducing Acute Exacerbation in GOLD Stage 3 or 4 COPD

COPD is a highly prevalent disease, with a prevalence among people 40 years of age or older of 10.1% worldwide and 13.7% in China. COPD has become the third leading cause of death worldwide. Frequent acute exacerbation and exercise limitation broadly exist in COPD patients, especially those in GOLD stage 3 or 4. Although appropriate pharmacological therapies have been proven to be effective in COPD management, however, many gaps are still to be filled. For example, the adverse effects of pharmacologic therapies can never be ignored. The investigator's previous studies suggested that traditional Chinese medicine (TCM) has effect on GOLD stage 3 or 4 COPD. This is a multicenter, randomized, double-blind, placebo controlled trial to evaluate the effect of Bufei Yishen granule on reducing acute exacerbation in GOLD stage 3 or 4 COPD subjects. After a 14-day run-in period, 348 subjects will be randomly assigned to treatment group or control group for 52-week treatment. The primary outcomes are frequency and duration of acute exacerbation. The secondary outcomes include mortality, pulmonary function, clinical symptoms, exercise capacity, quality of life and treatment satisfaction. Safety will also be assessed.