SAR131675 is a potent and selective small-molecule inhibitor of the vascular endothelial growth factor receptor 3 (VEGFR3), also known as Flt4. It is a pyrazol-1-yl-benzamide derivative designed to specifically target the tyrosine kinase activity of VEGFR3, which plays a crucial role in lymphangiogenesis. Its primary application is in oncology research, particularly for investigating the role of lymphangiogenesis and lymphatic metastasis in cancer progression. By inhibiting VEGFR3, SAR131675 blocks downstream signaling pathways, thereby suppressing the growth of lymphatic vessels associated with tumors. It has been used extensively as a research tool in preclinical studies to evaluate the therapeutic potential of VEGFR3 inhibition in various cancer models, including breast cancer and melanoma. While not an approved therapeutic itself, SAR131675 serves as a valuable pharmacological probe. Its high selectivity for VEGFR3 over other VEGFR family members (VEGFR1 and VEGFR2) makes it a key compound for dissecting the specific functions of this receptor in pathological and physiological contexts.