benralizumab + ustekinumab

This is a combination of two monoclonal antibody biologic drugs—benralizumab and ustekinumab—used as dual targeted therapy in patients with coexisting severe eosinophilic asthma and inflammatory bowel disease (such as ulcerative colitis). Benralizumab is a humanized IgG1k monoclonal antibody that targets the interleukin-5 receptor alpha (IL-5Rα) on eosinophils and basophils. It blocks IL-5 signaling and induces apoptosis of these cells via enhanced antibody-dependent cell-mediated cytotoxicity (ADCC), leading to rapid depletion of eosinophils. Ustekinumab is a fully human IgG1κ monoclonal antibody that binds to the p40 subunit shared by interleukin-12 (IL-12) and interleukin-23 (IL-23), inhibiting their activity and thus modulating immune responses involved in inflammatory bowel diseases. The combination has been reported in case studies for patients requiring simultaneous control of both diseases when monotherapy was insufficient. Both agents are approved individually for their respective indications; however, their combined use represents an off-label approach supported by emerging clinical experience.