FIIN-1

FIIN-1 (Fibroblast Growth Factor Receptor Irreversible Inhibitor-1) is a potent, first-generation covalent small molecule inhibitor of the fibroblast growth factor receptor (FGFR) family. It was developed as a research tool compound and is recognized as the first covalent inhibitor to target the conserved cysteine residue in the ATP-binding pocket of all four FGFR isoforms (FGFR1, FGFR2, FGFR3, and FGFR4). By forming a permanent bond with this cysteine, FIIN-1 provides sustained inhibition of FGFR signaling pathways, which are frequently dysregulated in various malignancies. While it also shows some activity against VEGFR family members such as Flt1 and Flt4, its primary application is in chemical biology to study FGFR-dependent cellular processes and to overcome resistance mutations, such as gatekeeper mutations, that limit the efficacy of reversible FGFR inhibitors. It is not currently being developed for clinical use.

Other names

FGFR irreversible inhibitor-1