Summary: Eosinophilic inflammation underlies chronic inflammatory process in more than 50% of patients diagnosed with bronchial asthma. In the respiratory tract eosinophils can directly induce bronchospasm, damage the respiratory epithelium, induce fibrosis of the intercellular space, smooth muscle growth and, as a consequence, enhance airway remodeling. In clinical practice, higher levels of eosinophils in peripheral blood are associated with a higher risk of asthma exacerbations. The results of randomized, placebo-controlled trials have proved the efficacy of benralizumab in the management of asthma. A decrease in the use of emergency medication, systemic and inhaled glucocorticosteroids and a significant reduction in the risk of exacerbations in patients with severe eosinophilic asthma was found. Post hoc analyzes of clinical trials point towards a rapid onset of efficacy and high safety profile of benralizumab. Already after the first dose, improvement in lung function parameters, decrease in symptoms, consumption of rescue medications and improvement of exercise tolerance were observed. The efficacy of benralizumab does not depend on the initial level of IgE and atopy status. The latest meta-analysis of the effectiveness of biological therapies influencing the IL-5 signaling pathway, taking into account the differences in clinical characteristics of patients included in consecutive trials, showed similar efficacy of benralizumab and mepolizumab considering the effect of these drugs on the decrease of exacerbations, hospitalization, ER visits and improvement in lung function parameters.