Lazertinib is primarily used in the treatment of non-small cell lung cancer (NSCLC), particularly for patients with epidermal growth factor receptor (EGFR) mutations. It functions as a third-generation EGFR tyrosine kinase inhibitor, targeting both common EGFR mutations and the T790M resistance mutation. This makes it effective in cases where earlier-generation EGFR inhibitors have failed. Lazertinib is known for its ability to penetrate the blood-brain barrier, making it useful in treating NSCLC with central nervous system metastases. Its selectivity helps minimize side effects compared to older treatments, improving patient outcomes and quality of life. Clinical trials have shown promising results in terms of tumor response rates and progression-free survival, positioning it as a valuable option in targeted cancer therapy.