Rociletinib (CNX-419) is an orally available small molecule, irreversible inhibitor of epidermal growth factor receptor (EGFR) with potential antineoplastic activity.

CO-1686 demonstrates significant dose-dependent tumor growth inhibition across all models of EGFR mutations, including transgenic mice expressing EGFRL858R- and EGFRL858R/T790M.

CO-1686 selectively inhibits the growth of NSCLC (non-small cell lung cancer) cells expressing mutant EGFR, with a GI50 range of 7 to 32 nM, and induces apoptosis. NSCLC cell lines resistant to CO-1686 show signs of epithelial-mesenchymal transition and increased sensitivity to AKT inhibitors. In cells expressing mutant EGFR, CO-1686 inhibits p-EGFR with an IC50 range of 62 to 187 nM, while also inhibiting EGFR phosphorylation in three types of cells expressing WT (wild type) EGFR, with an IC50 of >2,000 nM.

Inhibition Kinetics Studies: Recombinant human wild-type and T790M/L858R double mutant EGFR, both Nterminal GST-tagged, are used in the assay. The Omnia continuous read assay is performed as described by the vendor.

Cells are seeded at 3,000 cells per well in growth media supplemented with 5% FBS, 2 mmol/L, L-glutamine, and 1% penicillin–streptomycin, allowed to adhere overnight, and treated with a dilution series of test compounds for 72 hours. Cell viability is determined by CellTiter-Glo, and results are represented as background-subtracted relative light units normalized to a dimethyl sulfoxide (DMSO)–treated control. Growth inhibition (GI 50) values are determined by GraphPad Prism 5.04. MK-2206 and XL-880 compounds are obtained from Selleck Chemical. CI data are generated using CalcuSyn.(Only for Reference)