pertuzumab + topotecan

**Pertuzumab + topotecan** is an investigational combination regimen composed of two distinct antineoplastic agents—pertuzumab, a recombinant humanized monoclonal antibody targeting the human epidermal growth factor receptor 2 (HER2/ERBB2), and topotecan, a topoisomerase I inhibitor small molecule. Pertuzumab inhibits ligand-dependent heterodimerization of HER2 with other HER family members, resulting in blockade of downstream signaling pathways and reduced tumor cell proliferation. Topotecan interferes with the action of topoisomerase I, resulting in DNA damage and cell death. This combination would theoretically provide dual targeting—HER2 signal disruption and direct cytotoxicity through topoisomerase I inhibition. As of now, there is no evidence in the literature of published clinical trials or established indications for the combination of pertuzumab with topotecan, and no unique brand name for the combination exists.