The article is devoted to the creation of the prevention of severe course of COVID-19 molecular model from the standpoint of the Titov’s phylogenetic theory of general pathology. The role of the renin-angiotensin and kallikrein-kinin systems in the severe course of COVID-19 is discussed. Using the example of activation of the renin-angiotensin system in non-communicable diseases, the importance of controlling traditional risk factors for the prevention of severe COVID-19 is shown.