Ganitumab (AMG-479) is a fully human monoclonal IgG 1 antibody that binds insulin-like growth factor 1 receptor (IGF-I receptor) and is being evaluated in clinical studies as monotherapy and in combination with other agents. The IGF system ganitumab targets has been implicated in the risk of cancer in recent years, including evidence from epidemiological data, research in cancer models and knowledge of the downstream signaling pathways Ras/Raf/extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) and lipid kinase phosphatidylinositol 3-kinase (PI3K)/AKT, networks which are involved in cell proliferation and survival. As a result, various means of targeting the IGF-I receptor are being explored.