L19

**L19** is a human monoclonal antibody that specifically targets the ED-B domain of fibronectin, a marker of angiogenesis and tumor stroma expressed in the extracellular matrix of neoplastic tissues but absent in normal adult tissues. Developed by Philogen using immunocytokine and vascular targeting technologies, it serves as a targeting moiety for fusion proteins and conjugates designed to deliver cytokines or radionuclides selectively to tumor vasculature and sites of pathologic neovascularization, enhancing antitumor immune responses or enabling targeted radiotherapy while minimizing systemic toxicity.[1][2][4][6][8]