Rabe KF, et al. - In patients with moderate-to-severe chronic obstructive pulmonary disease (COPD) and chronic bronchitis who were enrolled in a randomized, double-blind, placebo-controlled trial conducted at 18 sites in 5 countries, researchers assessed the anti-inflammatory effects of roflumilast on bronchial mucosal inflammation. Patients were randomized (1:1) to either roflumilast 500 μg once daily or placebo for 16 weeks, in addition to bronchodilator therapy (inhaled corticosteroids were not permitted). Findings revealed no impact on the number of CD8 cells in bronchial submucosa roflumilast treatment vs placebo. However, according to bronchial biopsy samples and induced sputum, there were significant reductions in eosinophil cell counts. Based on these data, the authors postulated that the effect of roflumilast in COPD could be mediated by an effect on lung eosinophils.