Polyclonal and Monoclonal Antibodies for the Treatment and Prevention of Influenza

While at least 8 monoclonal and 3 polyclonal antibody products have been tested in clinical trials for the treatment of influenza, no products have been licensed, and most have stopped clinical development. The COVID-19 pandemic demonstrated that these approaches, especially monoclonal antibodies, may have unique potential in certain stages of disease and populations, especially in preventing severe disease in a population without preexisting immunity or in those with a limited capacity to mount an effective humoral immune response. This review summarizes past and ongoing efforts in using monoclonal and polyclonal antibodies for the treatment and prevention of influenza, focusing on products that have entered clinical trials and drawing lessons from COVID-19 to direct future efforts on these strategies.