Biochem/physiol Actions

NVP-AEW541 is a reversible, ATP-competitive, orally available insulin-like growth factor-I receptor (IGF-IR, IGF-1R) inhibitor that, despite its equipotency against recombinant kinase domains of insulin receptor (InsR) and IGF-IR in cell-free kinase assays (IC50 = 140 & 150 nM, respectively), exhibits high selectivity toward cellular autophosphorylation of endogenous full-length IGF-1R (IC50 = 86 nM) over InsR (IC50 = 2.3 µM), HER1, PDGFR, c-Kit, and Bcr-Abl p210 (IC50 >5 µM). AEW541 effectively inhibits IGF-IR-mediated signaling and cancer survival (IC50 = 105 nM/MCF-7 soft agar growth, 1.64 µM/NWT-21 proliferation) in cultures and tumor growth in vivo (20 to 50 mg/kg twice daily p.o.; NWT-21 fibrosarcoma & TC-71 musculoskeletal sarcoma xenografts in mice).