This article reviews clinical case of epidermal growth factor receptor (EGFR) mutation-positive non-small cell lung cancer and the usage of osimertinib for its treatment. Targeted drugs, EGFR tyrosine kinase inhibitors were approved for the treatment of non-small cell lung cancer more than 15 years ago*. Updated results of the large multicenter randomized FLAURA trial showed that osimertinib, a third-generation irreversible selective epidermal growth factor receptor tyrosine kinase inhibitor, was more effective than first-generation EGFR tyrosine kinase inhibitors, not only in terms of progression-free survival, but in terms of duration of response and overall survival. Furthermore, statistically and clinically significant benefit is achieved without deterioration of tolerance and quality of life. This article presents a clinical case of a woman who has taken part in this clinical trial. In light of the fact that this patient has been one of the first to receive this therapy in Russia, this experience appears to be interesting, because it allows assess the long-term results of the therapy: the achieved response duration is more than 50 months with good tolerance of therapy.