Model for competition from self during passive immunization, with application to broadly neutralizing antibodies for HIV

► We propose a mathematical model to interpret observations concerning the behavior of broadly neutralizing antibodies for chronic HIV in vivo. ► We use the model to fit patient data. ► The model enables us to identify a threshold antibody level that must be achieved to decrease the viral load effectively. ► In an appendix, we develop a model of passive immunization against influenza, and acute infection.