Acute systemic reactions including anaphylactic & hypersensitivity reactions (eg, anaphylaxis, angioedema, urticaria, papular urticaria, rash). Discontinue treatment permanently in the event of hypersensitivity reaction; if patient becomes infected w/ helminth while receiving therapy & does not respond to anti-helminth treatment. Not to be used to treat acute asthma exacerbations. Not to be inj into areas where skin is tender, bruised, erythematous or hardened. Avoid abrupt discontinuation. Patients w/ active organ threatening or life-threatening manifestations of EGPA. History of anaphylaxis unrelated to benralizumab. Monitor patients for appropriate time after administration of treatment. Treat patients w/ pre-existing helminth infections before initiating therapy. Avoid use during pregnancy. Lactation. Childn (<6 yr) & adolescents 6-17 yr w/ asthma; <18 yr w/ EGPA.