benralizumabi

Benralizumab is a humanized afucosylated monoclonal antibody that binds to the alpha chain of the interleukin-5 receptor (IL-5Rα) on the surface of eosinophils and basophils. By engaging Fc gamma receptors on natural killer cells, it induces antibody-dependent cellular cytotoxicity, leading to rapid depletion of eosinophils in blood and tissues. This mechanism targets eosinophil-driven inflammation in asthma.

Benralizumab is approved as add-on maintenance therapy for adults and adolescents 12 years and older with severe eosinophilic asthma. Clinical trials show reductions in asthma exacerbations, improvements in lung function, and better quality of life, with some patients able to reduce or discontinue daily oral corticosteroids. The standard dosing is 30 mg administered subcutaneously every 4 weeks for the first 3 doses, then every 8 weeks.

Administration is by subcutaneous injection, given in a clinical setting or by trained patients or caregivers where appropriate. Benralizumab has a long half-life, supporting the dosing schedule of every 8 weeks after the initial doses.

Common adverse events include injection-site reactions, headache, fever, and pharyngitis. Hypersensitivity reactions, including rare cases of anaphylaxis, have been reported. Because eosinophils contribute to defense against certain parasites, clinicians may consider local parasitic infection risk when initiating therapy in endemic areas.

Benralizumab was developed by AstraZeneca and approved by the U.S. Food and Drug Administration in 2017 for severe eosinophilic asthma, with approvals in other regions for the same indication. It is one of several anti-IL-5 pathway therapies, alongside agents such as mepolizumab and reslizumab.