C3 and COVID-19: Interestingly, C3 inhibition in patients with COVID-19 afforded broader therapeutic control by attenuating both C3a and sC5b-9 generation and preventing factor B consumption, which is associated with a more robust decline of neutrophil counts, attenuated neutrophil extracellular trap release, faster serum lactate dehydrogenase decline, and more prominent lymphocyte recovery (36).