cixutumumab + antiestrogen therapy

Cixutumumab + antiestrogen therapy is a combination regimen comprising cixutumumab, a fully human IgG1 monoclonal antibody against insulin-like growth factor-1 receptor (IGF-1R), and antiestrogen drugs (such as fulvestrant, exemestane, letrozole, anastrozole, or tamoxifen). Cixutumumab binds IGF-1R, blocking IGF-1 signaling and inhibiting the downstream PI3K/AKT pathway, leading to decreased proliferation and increased apoptosis of tumor cells. Antiestrogen agents act by antagonizing or downregulating the estrogen receptor, reducing estrogen-dependent cancer cell growth. This combination has been investigated in postmenopausal women with hormone receptor–positive, advanced or metastatic breast cancer progressing after prior antiestrogen therapy[1][3][5].