neratinib + paclitaxel + trastuzumab

This is a combination regimen consisting of three drugs—neratinib, paclitaxel, and trastuzumab—used primarily in the treatment of HER2-positive metastatic breast cancer. - **Neratinib** is an oral, irreversible small-molecule inhibitor targeting pan-HER (ErbB) receptor tyrosine kinases (HER1/EGFR, HER2, and HER4), blocking downstream signaling pathways involved in tumor cell proliferation and survival. - **Paclitaxel** is a microtubule-stabilizing chemotherapeutic agent that inhibits cell division by preventing microtubule depolymerization. - **Trastuzumab** is a monoclonal antibody that binds to the extracellular domain of the human epidermal growth factor receptor 2 (HER2), inhibiting its signaling and mediating antibody-dependent cellular cytotoxicity. The combination aims to provide dual anti-HER blockade with cytotoxic chemotherapy for enhanced efficacy in patients who have previously received anti-HER agents or taxanes. Clinical studies have shown this regimen can achieve significant clinical benefit even after prior exposure to similar therapies[2][7]. The most common adverse events include diarrhea (notably from neratinib), dehydration, electrolyte imbalance, and fatigue; primary diarrheal prophylaxis reduces severe diarrhea risk[2].