PHA-680632 is potent inhibitor of Aurora A, Aurora B and Aurora C with IC50 of 27 nM, 135 nM and 120 nM, respectively. It has 10- to 200-fold higher IC50 for FGFR1, FLT3, LCK, PLK1, STLK2, and VEGFR2/3. PHA-680632 is active on a wide range of cancer cell lines and shows significant tumor growth inhibition in different animal tumor models at well-tolerated doses. The mechanism of action of PHA-680632 is in agreement with inhibition of Aurora kinases. PHA-680632 in association with radiation leads to additive effects in cancer cells, especially in the p53-deficient cells. Combined ionising radiation (IR) and treatment of PHA-680632 (100–400 nM) prior to IR leads to an enhancement of radiation-induced Annexin V positive cells, micronuclei formation, and Brca1 foci formation only in HCT116 cells with deficient p53, other than the p53 wild-type counterparts. HA-680632 (15–60 mg/kg) inhibits tumor growth in mice xenografts models of HL60, A2780, and HCT116 cells, by reducing tumor cell proliferation and increasing apoptosis. PHA-680632 is the first representative of a new class of Aurora inhibitors with a high potential for further development as an anticancer therapeutic.