1. According to foreign data, the approved placebo-controlled double-blind comparative test results show that pirfenidone can inhibit the decline of vital capacity compared with the placebo group (see the table below for data). The object of this experiment is the patients clinically diagnosed as idiopathic pulmonary interstitial fibrosis. Before taking the medicine, the lowest value of SpO22 _ 2 is more than 85% when walking for 6 minutes with treadmill testing machine, which is more than 5% different from that at rest.

Comparison of changes in vital capacity (treated with pirfenidone or placebo for 52 weeks)

2. The latest ASCEND research published in NEJM (New England Journal of Medicine) shows that pirfenidone can effectively slow down the disease progress of patients with idiopathic pulmonary fibrosis after 52 weeks of treatment. Compared with the placebo group, the predicted value of forced vital capacity (FVC, the main index of lung function) in pirfenidone group decreased absolutely ≥ 10% or the patient mortality decreased by 47.9%, while FVC did not decrease or the patient mortality increased 132.5% (P

3. Tolerance test: The results of phase I tolerance test of healthy volunteers in China showed that

(1) Maximum tolerated dose of single dose: the maximum tolerated dose of single dose without adverse reactions is 400mg, and the maximum tolerated dose that fails to reach the termination index is 800 mg.

(2) Maximum tolerated dose for multiple administration: the maximum tolerated dose for multiple administration is 600mg each time, 1 time per day, and the cumulative dose per day is 1800 mg.