Pamufetinib

Pamufetinib (TAS-115) is a potent VEGFR and hepatocyte growth factor receptor (c-Met/HGFR)-targeted kinase inhibitor with IC₅₀s of 30 and 32 nM for rVEGFR2 and rMET, respectively. IC50 & Target: IC50: 30 nM (rVEGFR2), 32 nM (rMET)^[1] In Vitro: Pamufetinib is ATP antagonism with inhibition constant (K_i) values against rVEGFR2 and rMET of 12 and 39 nM, respectively. Pamufetinib inhibits the kinase activity of both VEGFR2 and MET and their signal-dependent cell growth as strongly as other known VEGFR or MET inhibitors. Pamufetinib induces less damage in various normal cells than do other VEGFR inhibitors^[1]. Pamufetinib does not affect the growth of PC-9 or HCC827 cells at concentrations less than 10 μM; however, the combined use of Pamufetinib with erlotinib reverses HGF-induced resistance in the cell lines in a concentration-dependent manner. Pamufetinib inhibits VEGF production by cancer cells and endothelial proliferation^[2]. In Vivo: Pamufetinib (50 mg/kg/d) completely prevents tumor growth during the treatment period. Pamufetinib (200 mg/kg/d) induces a 48% regression from the initial tumor volume in MET-amplified human cancer transplanted models. The estimated 50% effective dose (ED₅₀) of Pamufetinib in this model is 8 mg/kg/d. Pamufetinib significantly prolongs survival of these mice when administered at doses of 50 or 200 mg/kg/d^[1]. Pamufetinib inhibits angiogenesis in PC-9/HGF tumors in vivo. Moreover, the doublet erlotinib and Pamufetinib successfully inhibit PC-9/HGF tumor growth and delay tumor regrowth associated with sustained tumor vasculature inhibition even after cessation of the treatment^[2].