Methods and compositions for targeting disease related cell surface receptors using radiolabeled and/or cytotoxin labelled antibodies

A package or composition comprising a cytotoxic agent comprising a first antibody that specifically binds a target disease cell surface receptor, a cytotoxin, and a radiolabel,

• wherein the cytotoxin is linked directly to the antibody, and
• wherein the radiolabel comprises a radionuclide and optionally a scaffold, wherein the scaffold is directly coupled to the antibody,
• and a second cytotoxic agent,
• the second cytotoxic agent comprising a second antibody that specifically binds the target disease cell surface receptor,
• wherein the second cytotoxic agent comprises a second cytotoxin, wherein the second cytotoxin is linked directly to the second antibody and a second radiolabel, wherein the second radiolabel comprises a second radionuclide and a second scaffold, wherein the second scaffold is directly coupled to the second antibody,
• wherein the first antibody is trastuzumab and the second antibody is pertuzumab.