In the severe or fatal course of COVID-19, rapid virus replication gives rise to exuberant inflammatory response including cytokine storm, characterized by elevated plasma concentrations of proinflammatory cytokines that support neutrophil activity and stimulate endothelial cells. Рost mortem examinations confirm these data, indicating extensive neutrophil infiltration and accumulation of neutrophil extracellular traps (NET)s in lung tissues of patients who have died from COVID-19. In this paper the possibility of therapy with dornase-alfa in COVID-19 patients is discussed. Designed to treat cystic fibrosis lung disease, this drug can reduce neutrophil activity, slow down the NET release and accelerate the NET clearance in the airways of COVID-19 patients. The authors also present the protocol of COVID-19 therapy with dornase-alfa produced by Russian manufacturer.