Used in cancer therapy, particularly for targeting tumor angiogenesis. It inhibits Delta-like ligand 4 (DLL4), a key protein in the Notch signaling pathway, which plays a critical role in the formation of new blood vessels that supply tumors. By blocking DLL4, the antibody disrupts the development of tumor vasculature, leading to reduced blood flow and nutrient delivery to cancer cells. This results in inhibited tumor growth and can enhance the effectiveness of other anticancer treatments. It has shown potential in clinical studies for solid tumors, including colorectal and ovarian cancers. Its mechanism also promotes the normalization of remaining blood vessels, potentially improving drug delivery. Being a reference antibody, it is also used in research and development to benchmark new anti-DLL4 therapies.