Few drugs have shown consistent antiviral efficiency in vitro together with reported efficiency in patients infected with SARS-CoV-2 [3,12]. Of these, CLQ is of interest as its chemical structure is based on a combination of cationic nitrogen atoms and aromatic rings. Both features have been shown to be key determinants of the recognition of sialic acids and gangliosides by proteins [20,26]. Modelling approaches have been used successfully to decipher various molecular mechanisms of protein–sugar interactions accounting for the interaction of virus [27], bacteria [28], membrane [13] and amyloid proteins [20] with cell surface glycolipids. This in-silico strategy was applied to unravel the molecular mechanisms underlying the antiviral mechanisms of CLQ and CLQ-OH against SARS-CoV-2 infection. First, it was shown that CLQ and CLQ-OH bind readily to sialic acids with high affinity, including the typical 9-O-SIA subtype recognized by coronaviruses [23]. Next, it was shown that CLQ and CLQ-OH also bind to sialic-acid-containing gangliosides. Based on these data, the drugs may also recognize the sialic acid residues of glycoproteins. Further studies will help clarify this point.