The presence of glycosaminoglycan (GAG)-binding-like motifs in the RBD and S2 proteolytic cleavage sites of SARS-CoV-2 S-protein (28, 34), along with the promising anti-SARS-CoV-2 activity of heparin executed through competitive inhibition of its binding to cell surface HS, suggests a strong rationale for exploring the anti-COVID-19 activity of other sulfated glycans (either GAGs or GAG mimetics). This evidence concerns the gene PROS1 and COVID-19.