EGFR and neoplasm: In two phase 2 trials, the combination of dasatinib and erlotinib mediated tumour reductions in two EGFRm patients with acquired resistance, but overall response rates remained low.4,13,14 Based on our preclinical studies demonstrating improved in vivo efficacy of dasatinib and afatinib in T790M models of acquired resistance to first-generation EGFR TKI, we hypothesised that this combination would lead to durable disease control in EGFRm NSCLC patients with acquired TKI resistance.