Djamin RS, et al. - Researchers determined the predictors for best response to maintenance treatment with azithromycin in COPD patients with frequent exacerbations, focusing on patients' characteristics, in this investigation which was part of the COLUMBUS trial. The following features were noted in relation to a significant lower number of exacerbations per patient in the azithromycin group: baseline blood eosinophil count ≥2.0% vs < 2.0%, GOLD stage 1–2 vs GOLD stage 4 and GOLD group C vs group D. In patients, with a blood eosinophil count ≥2.0% vs an eosinophil count < 2.0% and in GOLD stages 1–2 vs stage 4, significantly lower number of hospitalizations were reported. Findings are suggestive of the efficacy of azithromycin maintenance treatment in COPD patients with frequent exacerbations, who were either categorized in GOLD stage 1–2 or GOLD C and those with a blood eosinophil count of ≥2.0%.