ACE2 and obesity due to melanocortin 4 receptor deficiency: ProHyperglycemia, typical in obesity and T2D, induces increased ADAM17 protein expression. Application of ADAM17 siRNA reduces SARS-CoV infectivity. ContraComorbidity of obesity and T2D with severity of COVID-19 was observed in viral infections other than SARS-CoV/CoV-2 and thus is not ACE2 specific. ADAM17 regulates the fusion of viral particles with cytoplasmic membranes involved in entering of SARS-CoV/CoV-2 into the host cells. Thus, the positive effect of ADAM17 suppression is not in an obvious way connected with a reduced ACE2 shedding.