ObjectiveTo evaluate the clinical efficacy and safety of pirfenidone in Chinese patients with idiopathic pulmonary fibrosis (IPF). MethodsIn a multicenter,randomized,double-blind,comparative clinical trial,87 patients with IPF were randomly divided into two groups. Group A (43 patients) were treated with pirfenidone (1 200 mg per day) for 48 weeks,while Group B (44 patients) were treated with placebo. Clinical features were compared between two groups including efficacy indicators (pulmonary function,6MWT,and quality of life scores) and safety indicators (incidence of adverse events). ResultsForced vital capacity (FVC) was increased by (90±410)mL in Group A and decreased by (70±310)mL in Group B (P<0.05);In Group A,forced expiratory volume in 1 second was raised by (100±330)mL and (110±240)mL following 12 and 24 weeks after treatment,significantly different from group B (P<0.05). There were significant differences in 6MWT between two groups 36 and 48 weeks after treatment respectively(both P<0.05). Quality of life scores,including the St. George's score (excluding symptoms) and dyspnea score,were significantly higher in Group A than Group B (both P<0.05). There was no significant difference in the incidence of adverse events between Groups A and B (83.72% vs. 72.73%,P>0.05). ConclusionDomestic pirfenidone is clinically effective and safe for the treatment of IPF in Chinese patients.