FIIN-2 is an irreversible FGFR inhibitor with IC50 values of 3.09, 4.3, 27, and 45.3 nM for FGFR1, FGFR2, FGFR3, and FGFR4, respectively. It has been shown to inhibit cell proliferation of transformed Ba/F3 cell lines and demonstrates antiproliferative activity in cells dependent upon the gatekeeper mutants of FGFR1 or FGFR2. By inhibiting FGFR in a zebrafish developmental model, FIIN-2 caused mild to severe alterations in tail morphogenesis similar to the phenotypes reported following genetic knockdown of FGFR.
