WZ3146 is a mutant-selective irreversible inhibitor of EGFR(L858R) and EGFR(E746_A750) with IC50 of 2 nM and 2 nM; does not inhibit ERBB2 phosphorylation (T798I).

EGFR (L858R):2 nM

WZ3146 significantly suppresses the growth of EGFR mutation containing cell lines with IC50 of 3 nM in EGFR Del E746_A750 containing HCC827 cells, 15 nM in EGFR Del E746_A750 containing PC9 cells, 29 nM in EGFR L858R/T790M containing H1975 cells and 3 nM in EGFR Del E746_A750/T790M containing PC9 GR cells. [1]

In-vitro inhibitory enzyme kinetic assays: The assays are carried out in triplicate using the ATP/NADH coupled assay system in a 96-well format. The final reaction mixture contains 0.5 mg/mL Bovine Serum Albumin (BSA), 2 mM MnCl2, 1 mM phospho(enol) pyruvic acid (PEP), 1 mM TCEP, 0.1 M Hepes 7.4, 2.5 mM poly-[Glu4Tyr1] peptide, 1/50 of the final reaction mixture volume of pyruvate kinase/lactic dehydrogenase enzymes from rabbit muscle, 0.5 mM NADH, 0.5 μM EGFR kinase, 100 μM ATP and varied amount of WZ3146. WZ3146 and ATP are mixed and made separate stock from the mixture with all other ingredients and added last to the latter to start the reaction. Steady state initial velocity data are drawn from the slopes of the A340 curves.

Growth and inhibition of growth is assessed by MTS assay. NSCLC or Ba/F3 cells are exposed to treatment for 72 hours and the number of cells used per experiment is determined empirically. All experimental points are set up in six to twelve wells and all experiments are repeated at least three times. The data is graphically displayed using GraphPad Prism version 5.0 for Windows. The curves are fitted using a non-linear regression model with a sigmoidal dose response.(Only for Reference)