They are, as described in Introduction: (1) Erb-hRNase, an immuno-pro-toxin that contains a nontoxic human RNase, which becomes toxic when tethered by the Erbicin moiety inside tumour cells (De Lorenzo et al, 2004a); (2) Erb-hcAb, a compact, reduced-size anti-ErbB2 antibody engineered with Erbicin and the essential parts of a human immunoglobulin (De Lorenzo et al, 2004b). The gene discussed is ESR2; the disease is neoplasm.