Real-life rapidity of benralizumab effects in patients with severe allergic eosinophilic asthma: Assessment of blood eosinophils, symptom control, lung function and oral corticosteroid intake after the first drug dose.

Benralizumab is a humanized monoclonal antibody which binds to the α subunit of the interleukin-5 (IL-5) receptor and to the FcγRIIIa receptor expressed by natural killer cells, thus suppressing the pro-eosinophil actions of IL-5 and triggering eosinophil apoptosis via the very effective mechanism of antibody-dependent cell-mediated cytotoxicity (ADCC). Because of its recent approval and introduction in clinical practice for the add-on biological therapy of severe eosinophilic asthma, real-life investigations are still lacking. In this regard, our present real-life study refers to 13 patients with severe allergic eosinophilic asthma, currently under treatment with benralizumab at the Respiratory Unit of "Magna Græcia" University Hospital located in Catanzaro, Italy. Already 4 weeks after the first subcutaneous injection of benralizumab at the dosage of 30 mg, blood eosinophil count rapidly dropped down from 814.7 ± 292.3 cells/μL to 51.3 ± 97.5 cells/μL (p < 0.0001). This relevant hematologic change was associated with quick and significant increases in asthma control test (ACT) score (from 15.31 ± 2.78 to 21.15 ± 3.58; p < 0.0001), pre-bronchodilator forced expiratory volume in 1 s (FEV1) (from 1441 ± 757.9 mL to 1887 ± 837.3 mL; p < 0.001), and morning peak expiratory flow (PEF) (from 4.21 ± 2.20 to 5.33 ± 1.99 L/sec; p < 0.01). Furthermore, the marked improvement in global health status experienced by our patients allowed them to progressively lower and then completely interrupt, within 4 weeks, their daily intake of oral corticosteroids (OCS), which thereby fell from 15.58 ± 8.30 to 0 mg (p < 0.0001) of prednisone. Therefore, such preliminary results suggest that in patients with severe allergic eosinophilic asthma benralizumab can exert, within a real-life context, a very rapid and effective therapeutic action, already detectable 4 weeks after the first drug administration.