Avitinib (AC0010) is primarily used in the treatment of non-small cell lung cancer (NSCLC), particularly for patients with EGFR mutations. It functions as a tyrosine kinase inhibitor, targeting and blocking the activity of mutated EGFR proteins that drive cancer cell growth. This helps to slow down or stop the progression of the disease. It is often considered when patients develop resistance to first-line EGFR inhibitors like gefitinib or erlotinib. Additionally, Avitinib is being studied for its potential efficacy in other types of cancers where EGFR mutations play a significant role. Its application is closely monitored to manage side effects and ensure optimal therapeutic outcomes.