INCB126503

INCB126503 is an orally active and selective inhibitor of FGFR2/3, with IC50 values of 70 nM for FGFR1, 2.1 nM for FGFR2, 1.2 nM for FGFR3, 0.92 nM for FGFR3-V555L, 0.85 nM for FGFR3-V555M, and 64 nM for FGFR4. This compound inhibits FGFR signaling in vivo without causing hyperphosphatemia and demonstrates antitumor efficacy in xenograft models with FGFR3 genetic alterations.