Like CF, COPD is characterized by small airway mucus obstruction that is associated with accelerated loss of lung function and mortality. Our preliminary data indicate that cigarette smoke exerts deleterious effects on airway epithelial function including the reduction of CFTR activity, enhanced mucus expression, and a pronounced reduction in mucociliary transport (MCT). Preliminary data also indicate that approximately 50% of patients with COPD have reduced CFTR activity, as detected in the upper airways, lower airways, and sweat glands. Furthermore, CFTR dysfunction is independently associated with chronic bronchitis, can persist despite smoking cessation, and can be reversed by the CFTR potentiator ivacaftor (VX-770) in vitro by activating wild-type CFTR, resulting in a robust increase in MCT. Combined with unprecedented clinical improvement via augmented mucociliary clearance in CF patients with a responsive CFTR mutation treated with ivacaftor, these data indicate that CFTR represents a viable therapeutic target to address mucus stasis in a large subset of COPD patients (potentially representing over 4 million patients in the U.S. alone). This project will investigate the hypothesis that ivacaftor can augment CFTR activity in individuals with COPD who exhibit chronic bronchitis, resulting in meaningful improvements in epithelial function and respiratory health. Our initial pilot study in patients with COPD and chronic bronchitis demonstrated that ivacaftor was safe, demonstrated stable pharmacokinetics, and exhibited a trend towards efficacy in patient-reported outcomes (PROs) and sweat chloride. The current trial will test the safety, pharmacokinetics, and pharmacodynamics of ivacaftor in a larger number of COPD patients with chronic bronchitis and for a longer treatment period, evaluating the potential of CFTR potentiator therapy to address acquired CFTR dysfunction in this population and set the stage for larger and longer-term trials in the future.
The purpose of this protocol is to test the safety, pharmacokinetics, and pharmacodynamics of the Cystic fibrosis transmembrane conductance regulator (CFTR) potentiator, ivacaftor in patients with chronic obstructive pulmonary disease (COPD) and chronic bronchitis. This project will investigate the hypothesis that ivacaftor can augment CFTR activity in individuals with COPD who exhibit chronic bronchitis, resulting in meaningful improvements in epithelial function and respiratory health. The study is a multicenter, randomized, double-blind, placebo-controlled, stratified study of orally-administered ivacaftor.