Based on currently available data on adding inhaled corticosteroids (ICS) to a LABA, ICS might be added to a LABA/LAMA combination in exacerbating patients who have an asthma-COPD overlap syndrome or high blood eosinophil counts, while in exacerbators with chronic bronchitis, consideration should be given to treating with a phosphodiesterase (PDE)-4 inhibitor (roflumilast) or high-dose mucolytic agents. The gene discussed is PDE4A; the disease is chronic obstructive pulmonary disease.