epirubicin + paclitaxel + trastuzumab

This is a combination regimen consisting of three drugs—epirubicin, paclitaxel, and trastuzumab—used primarily in the treatment of HER2-positive breast cancer. - **Epirubicin** is an anthracycline antibiotic that intercalates DNA strands and inhibits topoisomerase II, leading to inhibition of DNA replication and cell death. It is structurally related to doxorubicin but has a lower rate of cardiac toxicity[1][3]. - **Paclitaxel** is a taxane-class chemotherapeutic agent that stabilizes microtubules and prevents their depolymerization, thereby inhibiting cell division[1][2][3]. - **Trastuzumab** is a monoclonal antibody targeting the human epidermal growth factor receptor 2 (HER2). It binds to HER2 on cancer cells, blocking downstream signaling pathways involved in cell proliferation and survival; it also mediates antibody-dependent cellular cytotoxicity against tumor cells overexpressing HER2[6][7]. This combination leverages the cytotoxic effects of epirubicin and paclitaxel with the targeted action of trastuzumab for improved efficacy in patients with HER2-positive metastatic or early-stage breast cancer. The regimen may be used as first-line therapy or as part of adjuvant treatment protocols.