Indeed, C3 specific inhibitors using peptides and nanobodies platforms have been developed and clinical trials conducted in a large panel of diseases including periodontal inflammation and COVID-19 with AMY-101 (27, 28), in paroxysmal nocturnal haemoglobinuria with pegcetacoplan (29), and in acute antibody-mediated graft injury and age-related macular degeneration with Cp40 (30, 31). This evidence concerns the gene C3 and COVID-19.