SU5402 is a potent and selective vascular endothelial growth factor receptor (VEGFR) and fibroblast growth factor receptor (FGFR) inhibitor. Multiple myeloma studies suggest that SU5402 inhibits FGFR3 phosphorylation in-vitro. Additionally, SU5402 has been observed to inhibit IL-1 beta-induced MAPK activity.