Sapitinib (AZD-8931) , a reversible, ATP competitive inhibitor of EGFR(IC50=4 nM), ErbB2(IC50=3 nM) and ErbB3(IC50=4 nM), is more effective over Gefitinib or Lapatinib against NSCLC cell, 100-fold more specific for the ErbB family over MNK1 and Flt.

ERB3:4 nM, ErbB2:3 nM, EGFR:4 nM

Sapitinib shows different potency to NSCLC and SCCHN cell lines. Sapitinib has high sensitivity to PC-9 cells (EGFR activating mutation) with GI50 of 0.1 nM and low activity to NCI-1437 cells with GI50 above 10 μM. Sapitinib exhibits more potency against phospho-EGFR, phospho-erbB2 and phospho-erbB3 than either lapatinib or gefitinib in PE/CA-PJ41, PE/CA-PJ49, DOK and FaDu cells. [1]

Sapitinib reveals antitumor activity in BT474c, Calu-3, LoVo, FaDu and PC-9 xenografts. Sapitinib could reduce p-Akt, Ki67 expression and p-ERK in BT474c xenografts following acute treatment. Sapitinib also causes induction of the M30 apoptosis marker. Furthermore, Sapitinib shows greater proapoptotic effect compared with gefitinib and lapatinib in LoVo xenografts. [1]

Isolated kinase assays: The intracellular kinase domains of human EGFR and erbB2 are cloned and expressed in the baculovirus/Sf21 system. The inhibitory activity of AZD8931 is determined with ATP at Km concentrations (0.4 mM for erbB2 and 2 mM for EGFR) using the ELISA method.

To determine the antiproliferative activity against cell lines grown in vitro, AZD8931 is tested in a panel of NSCLC and SCCHN cell lines. Cells are incubated for 96 hours with AZD8931 (0.001-10 μM). Viable cell number is determined by 4 hours of incubation with MTS Colorimetric Assay reagent and absorbance measured at 490 nm on a spectrophotometer. (Only for Reference)