New expectations rose when recent reports revealed significant reductions in admissions to ICU and mortality in DPP4 inhibitor users of up to 24% [59,60,61,62,63], with several authors suggesting that targeting DPP4 could be a pharmacologically important strategy for treating patients suffering from severe respiratory diseases related to coronaviruses and COVID-19 [64,65]. The gene discussed is DPP4; the disease is respiratory system disorder.