tixagevimab + cilgavimab (AstraZeneca)

Tixagevimab + cilgavimab (sold under the brand name Evusheld) is a combination of two long-acting, recombinant human IgG1 monoclonal antibodies, tixagevimab and cilgavimab, directed against the spike protein of SARS-CoV-2. Discovered by Vanderbilt University Medical Center and developed by AstraZeneca, the antibodies bind to distinct, non-overlapping epitopes on the receptor-binding domain (RBD) of the viral spike protein, preventing interaction with the host cell's angiotensin-converting enzyme 2 (ACE2) receptor and neutralizing the virus. The antibodies were engineered with a triple-mutation (YTE) in the Fc region to extend their half-life and reduce Fc receptor and complement C1q binding to minimize the risk of antibody-dependent enhancement of disease. Initially authorized under Emergency Use Authorization (EUA) by the US FDA in December 2021 and approved in the EU and Japan for the pre-exposure prophylaxis and treatment of COVID-19, its authorizations were subsequently withdrawn globally (including by the FDA in January 2023 and the European Commission in September 2025) due to a lack of neutralizing activity against dominant, newly emerged SARS-CoV-2 Omicron subvariants.

Brand names

Evusheld

Other names

cilgavimab + tixagevimabtixagevimab + cilgavimabtixagevimab and cilgavimabtixagevimab/cilgavimab