A Multicenter Randomized Controlled Trial of Zephyr Endobronchial Valve Treatment in Heterogeneous Emphysema (LIBERATE)

Rationale: This is the first multicenter randomized controlled trial to evaluate the effectiveness and safety of Zephyr Endobronchial Valve (EBV) in patients with little to no collateral ventilation out to 12 months. Objectives: To evaluate the effectiveness and safety of Zephyr EBV in heterogeneous emphysema with little to no collateral ventilation in the treated lobe. Methods: Subjects were enrolled with a 2:1 randomization (EBV/standard of care [SoC]) at 24 sites. Primary outcome at 12 months was the Delta EBV-SoC of subjects with a post-bronchodilator FEV1 improvement from baseline of greater than or equal to 15%. Secondary endpoints included absolute changes in post-bronchodilator FEV1, 6-minute-walk distance, and St. George's Respiratory Questionnaire scores. Measurements and Main Results: A total of 190 subjects (128 EBV and 62 SoC) were randomized. At 12 months, 47.7% EBV and 16.8% SoC subjects had a Delta FEV1 greater than or equal to 15% (P <0.001). DEBV-SoC at 12 months was statistically and clinically significant: for FEV1, 0.106 L (P <0.001); 6-minute-walk distance, +39.31 m (P = 0.002); and St. George's Respiratory Questionnaire, -7.05 points (P = 0.004). Significant DEBV-SoC were also observed in hyperinflation (residual volume, -522 ml; P <0.001), modified Medical Research Council Dyspnea Scale (-0.8 points; P