Semaxanib (SU5416) is primarily used in research settings to study its potential as an angiogenesis inhibitor. It targets vascular endothelial growth factor (VEGF) receptors, making it a candidate for investigating treatments in diseases driven by abnormal blood vessel formation, such as cancer. By blocking VEGF signaling, it helps researchers understand how to control tumor growth and metastasis. Additionally, it has been explored in preclinical studies for its role in reducing inflammation and its potential application in conditions like rheumatoid arthritis. Its use remains largely experimental, focusing on uncovering mechanisms of angiogenesis and developing novel therapeutic strategies.