Used primarily in the treatment of non-small cell lung cancer, this compound functions as an inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase. It blocks signaling pathways involved in cell proliferation and survival, leading to reduced tumor growth. It is particularly effective in patients with specific EGFR mutations. Administered orally, it has shown clinical benefit in improving progression-free survival and overall response rates in targeted patient populations. Its application is a key example of personalized medicine in oncology.