Fruquintinib is a highly potent and selective VEGFR 1/2/3 inhibitor with IC50s of 33, 0.35, and 35 nM, respectively.  VEGF/VEGFR signal has been proven to be an important target for development of novel cancer therapies. One challenging aspect in VEGFR inhibitors is to achieve sustained target inhibition at tolerable doses previously seen only with the long-acting biologics.