The effect of roflumilast in addition to LABA/LAMA/ICS treatment in COPD patients.

Abstract

To the Editor: Recently, roflumilast has been added as a therapeutic option for chronic obstructive pulmonary disease (COPD). Roflumilast is a selective phosphodiesterase type 4 (PDE4) inhibitor [1]. The main concern of the large-scale studies performed was that they did not assess the effect of roflumilast in addition to a combination product such as long-acting β2-agonists (LABA) or long-acting muscarinic agents (LAMA) combined with inhaled corticosteroids (ICS) [2]. A novel technology called functional respiratory imaging (FRI) defines, in great detail, lung geometry and regional changes in airway volume and resistance [3–5]. By assessing changes close to the site of action of the intervention, the method is more sensitive (higher effect size) compared with standard pulmonary function tests (PFT) [3]. This implies that the mode of action of an intervention can be assessed in a small number of patients, while maintaining sufficient power to have statistically significant results [3, 4]. We performed a study aimed at investigating the mode of action of roflumilast in COPD patients on top of triple therapy (LABA/LAMA/ICS), using PFT, exercise tolerance tests, patient-reported outcomes (PRO) and FRI. The hypothesis was that roflumilast provides a large benefit to a subset of COPD patients and that FRI can assist in phenotyping these responders. Ideally, a PFT parameter could be defined that could identify the responding phenotype. A …