It is a well-designed multicentre, phase 2, double-blind, randomised, double-dummy, active placebo-controlled, multicentre study.

Currently, considering pharmacoeconomic factors and taking into account the high budgetary impact of their introduction into therapy, it seems necessary to use IL-5 inhibitors (such as benralizumab) prioritising patients with severe refractory eosinophilic asthma with eosinophilia (≥500 cells/μL in blood), where efficacy and efficiency are clearly superior to the rest. In patients with severe, refractory eosinophilic asthma, with thoseinophil levels <500 cells/μL, but with more than two severe exacerbations in the past year requiring the use of ≥2 cycles of oral or systemic corticosteroids or increased maintenance dose of the same for at least 3 days, or more than 1 severe exacerbation requiring hospitalisation, ICU admission or mechanical ventilation, the use of benralizumab or another IL-5 could be considered on an individual basis if very poor asthma control refractory to other available options is observed.

The use of benralizumab after an exacerbation is being studied in this paper. There are favourable precedents such as the study by Nowak et al. In this randomised, double-blind, placebo-controlled study, when added to usual care, 1 dose of benralizumab reduced the rate and severity of exacerbations experienced over 12 weeks by subjects presenting to the emergency department with asthma attacks. The drug can be said to be effective in preventing future exacerbations.

The mean number of previous exacerbations in the control group treated with prednisone is higher than in the benralizumab-treated group and the benralizumab + prednisone-treated group.

The adherence to background inhaled medication in all groups is not specified.

Benralizumab, which is a long half-life monoclonal antibody, is compared with prednisone with a 5-day duration of steroid therapy at discharge.

The COPD group is very small and I don't think the conclusions can be extrapolated to this one. There are clinical trials of this drug in COPD that failed to demonstrate the primary endpoint of reducing exacerbations.

Bronchial asthma is a common disease, with a prevalence in industrialised countries of 10-13% of the population. In the last 10 years, the prevalence has doubled in Western European countries and, in addition, 27% of the asthmatic population has needed care for an exacerbation in the previous year. This last circumstance may be due to the fact that clinical management of the asthmatic population is poor in Europe, as in the US. Asthma exacerbations are a frequent phenomenon and are important, so applying a drug such as benralizumab in these situations would require a broader pharmacoeconomic (cost-effectiveness) study. It would be necessary to go to the prevention of these better and to select somewhat better which patients we should treat with benralizumab within this exacerbating phenotype. Currently, with its current indications, we have this drug for severe eosinophilic asthma and in this series there is a possible mix of patients in terms of severity (according to the data, triple therapy understood as Ci+LABA +LAMA made up 42%-50% of cases).