Effect of Pirfenidone on Treatment-emergent (TE) All-cause Mortality (ACM) in Patients with Idiopathic Pulmonary Fibrosis (IPF): Pooled Data Analysis from ASCEND and CAPACITY

Background: Pooled analysis of the ASCEND and CAPACITY studies showed a significant reduction in the risk of ACM over 52 weeks in patients with IPF treated with pirfenidone compared with placebo, and a non-significant trend favoring pirfenidone over the entire study period (up to week 120). Objective: To evaluate TE ACM over the full duration of observation in the pooled population from ASCEND and CAPACITY. Methods: TE ACM at last vital status assessment was evaluated in 1247 patients. TE deaths occurred after the first pirfenidone dose and within 28 days of the last dose. Kaplan-Meier estimates were used to summarize survival time. Results: At week 120, TE ACM occurred in 27/623 (4.3%) patients on pirfenidone compared with 44/624 (7.1%) on placebo. The most common cause of death in both treatment groups was IPF (1.6% and 3.4% for pirfenidone and placebo, respectively). The TE ACM rate was lower on pirfenidone, compared to placebo, with a 38% reduction in the risk of TE ACM over 120 weeks (HR=0.62; 95% CI, 0.39–1.01; P=0.0515; (Figure). Estimates of TE ACM after week 96 are associated with higher uncertainty since few patients remained thereafter in the study. Conclusions: Pooled outcome analysis of the ASCEND and CAPACITY studies showed a clear trend towards reduced risk of TE ACM in patients with IPF treated with pirfenidone.