In vitro activity: AZD0364 is a potent and selective oral inhibitor of ERK1/2 that is efficacious in both monotherapy and combination therapy in models of NSCLC. AZD0364 exhibits high cellular potency against a direct substrate (e.g., inhibition of phosphorylation of p90RSK in BRAF mutant A375 cells, IC50 = 6 nM) and is highly selective (10/329 kinases tested are inhibited at>50% at 1 μM). In an unbiased cell proliferation screen of 750 tumor cell lines,>50% of cell lines that are sensitive to AZD0364 have RAS/MAPK pathway genetic alterations such as BRAF, NRAS or KRAS mutations. In a subset of KRAS mutant NSCLC cell lines, combined treatment of AZD0364 and selumetinib (AZD6244, ARRY-142886) is highly synergistic.

Kinase Assay: AZD-0364 is measured in the ERK2 mass spectrometry and A375 phospho-p90RSK assays with IC50s of 0.6 nM and 5.7 nM, respectively. AZD-0364 can inhibit the growth of a panel of cancer cell lines (A549, H2122, H2009, and Calu6 cell lines) with KRAS mutations as a monotherapy and this effect is synergistically enhanced by treatment with Selumetinib.

Cell Assay: KRAS-mutant Non-Small Cell Lung Cancer (NSCLC) A549, H2122, H2009, and Calu6 cell lines are seeded in 384-well black, clear bottomed plates, cultured for 18-24 hours and treated with increasing concentrations of AZD-0364 (7.143 nM, 61 nM, 357 nM, 2.143 μM and 10 μM) and Selumetinib (0-10 μM) in a 6×6 dosing matrix. Cells are seeded at a concentration such that cells in untreated wells are approximately 80% confluent at the end of the assay. After 3 days of treatment, live cell number is determined using a Sytox Green endpoint