During the preparation of this manuscript, Farzan and colleagues published a study [43] that describes inhibitors of HIV infection comprising CD4 domains 1 and 2 fused to the human IgG-1 Fc domain and to a sulfo-peptide derived from a HIV-1 neutralizing antibody that binds Env in a manner similar to that of CCR5-derived peptides. Here, CD4 is linked to HIV infectious disease.