To provide more accurate and stronger evidence for the efficacy of anti-IL-5 therapy in eosinophilic COPD patients, the current study differs in two ways from the previous meta-analysis (Dave and Arjun, 2021): we only included eosinophilic COPD patients (peripheral blood eosinophil count of 3% or more or >150 cells per cubic millimeter) (Balkissoon, 2018); we compared anti-IL-5 therapy in eosinophilic COPD and in asthma, which enabled a more robust assessment of the effect of anti-IL-5 therapy in eosinophilic COPD patients. This evidence concerns the gene IL5 and chronic obstructive pulmonary disease.