Figitumumab is a monoclonal antibody that targets the insulin-like growth factor 1 receptor (IGF-1R), which plays a key role in cell proliferation, survival, and metabolism. It has been investigated primarily in oncology for its potential to inhibit tumor growth in cancers where the IGF-1R pathway is overactive. This includes certain types of sarcomas, non-small cell lung cancer, and other solid tumors. The antibody works by blocking IGF-1R signaling, leading to reduced cancer cell growth and increased apoptosis. It has been studied in clinical trials both as a monotherapy and in combination with other anticancer agents, such as chemotherapy or targeted therapies like EGFR inhibitors, to enhance antitumor effects. Despite showing promise in early-phase trials, development of figitumumab was largely discontinued due to limited efficacy in later-stage studies and challenges related to patient selection and biomarker identification. However, it remains a reference antibody used in research to study IGF-1R biology and signaling pathways in cancer and metabolic diseases.