Design, Synthesis, and Antitumor Activity of Potent and Selective EGFR L858R/T790M Inhibitors and Identification of a Combination Therapy to Overcome Acquired Resistance in Models of Non-small-cell Lung Cancer

Epidermal growth factor receptor (EGFR) is one of the most studied drug targets for the treatment of non-small-cell lung Cancer (NSCLC). Here, we report the identification, structure optimization, and structure-activity relationship studies of quinazoline derivatives as novel selective EGFR L858R/T790M inhibitors. The most promising compound, 28f, exhibited strong inhibitory activity against EGFR L858R/T790M (IC₅₀ = 3.5 nM) and greater than 368-fold selectivity over EGFR WT (IC₅₀ = 1290 nM), a 6.7-fold improvement over osimertinib. Furthermore, 28f effectively inhibited downstream signaling pathways and induced Apoptosis in mutant cells. In the H1975 xenograft in vivo model, 28f exhibited a good tumor suppressive effect. Furthermore, the combination of 28f with the Ack1 Inhibitor dasatinib produced synergistic antiproliferative efficacy with 28f in 28f-resistant cells and in vivo. In conclusion,28f could become a candidate drug for the treatment of NSCLC, and the combination of 28f and dasatinib is expected to overcome EGFR resistance.