AZD3759 is a potent and selective inhibitor of the epidermal growth factor receptor (EGFR), specifically designed to target non-small cell lung cancer (NSCLC) with EGFR mutations. It demonstrates strong central nervous system (CNS) penetration, making it effective in treating brain metastases, which are common in advanced NSCLC. This property is particularly valuable because many EGFR inhibitors fail to cross the blood-brain barrier effectively. In clinical settings, AZD3759 has shown antitumor activity in patients with EGFR-mutated NSCLC that has spread to the brain. It is being investigated for use in early-stage trials, especially for patients who have developed resistance to first- or second-generation EGFR inhibitors. Its ability to achieve therapeutic concentrations in the brain offers a promising approach to controlling both systemic and CNS disease progression. Research continues to explore optimal dosing and combination strategies to enhance efficacy and manage resistance.