BO-264 is a highly potent and orally active transforming acidic coiled-coil 3 (TACC3) inhibitor with an IC50 of 188 nM and a Kd of 1.5 nM. BO-264 specifically blocks the function of FGFR3-TACC3 fusion protein. BO-264 induces spindle assembly checkpoint (SAC)-dependent mitotic arrest, DNA damage and apoptosis. BO-264 has broad-spectrum antitumor activity.