tucatinib + etoposide + trastuzumab

This is a combination therapy consisting of tucatinib, etoposide, and trastuzumab. Tucatinib is an oral small molecule tyrosine kinase inhibitor highly selective for the HER2 receptor, blocking its intracellular kinase domain to inhibit downstream signaling pathways such as PI3K and MAPK, leading to cell cycle arrest and apoptosis. Trastuzumab is a monoclonal antibody that binds to the extracellular domain IV of the HER2 receptor on tumor cells, blocking dimerization and activating immune-mediated cytotoxicity. Etoposide (VP16) is a small molecule chemotherapeutic agent that inhibits topoisomerase II, causing DNA strand breaks and preventing cancer cell replication. This combination has been studied in patients with HER2-positive metastatic breast cancer who have progressed after prior anti-HER2 therapies or cannot tolerate capecitabine[1][2][7]. The rationale for this regimen includes targeting both extracellular and intracellular domains of HER2 while adding cytotoxic chemotherapy[5].

Brand names

no widely used brand name for oral etoposide (VP16)

Other names

VP16 (for etoposide)