Sapitinib

Sapitinib (AZD-8931) is a reversible, ATP competitive EGFR inhibitor of with IC₅₀s of 4, 3 and 4 nM for EGFR, ErbB2 and ErbB3 in cells, respectively. IC50 & Target:IC50: 4 nM (EGFR), 3 nM (ErbB2), 4 nM (ErbB3)^[1] In Vitro: AZD8931 shows potent inhibitory effect on erbB2 in the ligand-independent MCF-7 cl24 cells, with IC₅₀ of 59 nM^[1]. AZD8931 (1 μM) has no significant effect on EGFR expression level, but significantly inhibits phosphorylation of Akt in a time- and dose-dependent manner in both SUM149 and FC-IBC-02 cells. AZD8931 (0.01, 0.1, 1, or 2 μM) inhibits proliferation and induces apoptosis in human IBC cells^[2]. At the cellular level, AZD8931 inhibits EGF-stimulated phosphorylation of EGFR in the KB cell line (IC₅₀: 4 nM) and heregulin-stimulated phosphorylation of HER2 (IC₅₀: 3 nM) and HER3 (IC₅₀: 4 nM) in the MCF-7 cell line. However, AZD8931 exhibits no CYP P450 inhibition (IC₅₀ > 10 μM against 1A2, 2C9, 2C19, 2D6, and 3A4)^[3]. In Vivo: AZD8931 (6.25-50 mg/kg, p.o.) significantly inhibits BT474c (breast), Calu-3 (NSCLC), LoVo (colorectal), FaDu (SCCHN), and PC-9 (NSCLC) tumor xenograft growth. AZD8931 is active in xenograft tumor models responsive to EGFR inhibition alone (LoVo and PC-9) or EGFR or erbB2 inhibition (BT474c, Calu-3, and FaDu). AZD8931 causes pharmacodynamic changes in proliferation and apoptosis markers in human tumor xenograft models^[1]. AZD8931 (25 mg/kg, p.o.) significantly inhibits the growth of SUM149 and FC-IBC-02 cells in vivo in SCID mice^[2]. AZD8931 displays favorable oral pharmacokinetics in rat and dog (low clearance and good bioavailability) and low human hepatocyte turnover (Clint < 4.5 μL/min/106 cells). In nude mouse after oral administration at 50 mg/kg, AZD8931 shows improved exposure, and at at 100 mg/kg oral dose once daily, it shows potent tumor growth inhibition activity in the LoVo mouse xenograft model^[3].