Chitosan-coated osimertinib-loaded biodegradable polymeric NPs targeting the EGFR T790M NSCLC mutant form were proven to have a 2.6- and 2.4-fold superior activity compared to plain osimertinib in H1975 mice models (cell line with epithelial morphology, isolated in 1988 from the lungs of a non-smoking female with NSCLC). This evidence concerns the gene EGFR and non-small cell lung carcinoma.