AGT and COVID-19: Although viral neutralization by preventing the binding of the SARS-COV-2 spike protein RBD to the host ACE2 has been the fundamental approach for the development of most COVID-19 therapeutic antibodies, researchers are also looking into other strategies with targets such as cytokines (GM-CSF, IL-6, IL-17A), angiotensin II (Ang II), tumor necrosis factor (TNF), inhibitory immune checkpoints (PD-1), and complement components (C5, C5a, C5aR) (137).