trastuzumab + letrozole

Trastuzumab + letrozole is a combination therapy used primarily for the treatment of advanced or metastatic breast cancer that is both HER2-positive and hormone receptor (estrogen and/or progesterone) positive. Trastuzumab is a monoclonal antibody that targets the human epidermal growth factor receptor 2 (HER2), inhibiting its signaling pathways, inducing cell cycle arrest, and mediating antibody-dependent cellular cytotoxicity. Letrozole is an aromatase inhibitor that suppresses estrogen synthesis by inhibiting the aromatase enzyme, thereby reducing estrogen-driven tumor growth. The combination addresses cross-talk between HER2 and estrogen receptor pathways, which can contribute to resistance to endocrine therapy alone. This regimen has demonstrated clinical benefit in patients with HER2+ and ER+ advanced breast cancer[1][4][6].

Brand names

FemaraHerceptin

Other names

letrozole + trastuzumab