cyclophosphamide + epirubicin + pyrotinib

Cyclophosphamide + epirubicin + pyrotinib is a combination therapy used in the treatment of HER2-positive breast cancer, particularly in neoadjuvant settings. This regimen combines a traditional chemotherapy backbone (cyclophosphamide and epirubicin) with pyrotinib, an irreversible pan-ErbB receptor tyrosine kinase inhibitor that targets HER1, HER2, and HER4. The combination has shown promising efficacy in achieving pathological complete response (pCR) in HER2-positive breast cancer patients. Pyrotinib works by covalently binding to ATP binding sites in intracellular kinases of HER1, HER2, and HER4, blocking downstream signaling pathways to inhibit tumor cell growth. The combination has demonstrated manageable safety profiles with diarrhea being the most common adverse event.