Mechanisms of resistance to osimertinib

Area of Science:

• Oncology
• Pharmacology
• Genetics

Background:

• Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have advanced treatment for advanced non-small cell lung cancer (NSCLC) with EGFR mutations.
• The T790M mutation is a primary resistance mechanism to first- and second-generation EGFR-TKIs.
• Osimertinib, a third-generation EGFR-TKI, targets sensitizing mutations and T790M.

Purpose of the Study:

• To review the clinical development of osimertinib for NSCLC treatment.
• To explore identified mechanisms of acquired resistance to osimertinib.
• To discuss ongoing strategies to overcome osimertinib resistance.

Main Methods:

• Review of clinical trial data, including the FLAURA study.
• Analysis of mechanisms of acquired resistance to osimertinib.
• Evaluation of emerging strategies to manage osimertinib resistance.

Main Results:

• Osimertinib is approved for EGFR T790M mutation-positive NSCLC post-EGFR TKI therapy.
• First-line osimertinib significantly improves progression-free survival (PFS) in EGFR-mutant NSCLC compared to first-generation EGFR-TKIs.
• Osimertinib demonstrates notable central nervous system (CNS) activity and a favorable safety profile.

Conclusions:

• Osimertinib represents a significant advancement in EGFR-mutated NSCLC treatment, both in first-line and subsequent settings.
• Understanding and overcoming acquired resistance mechanisms are crucial for long-term patient benefit.
• Ongoing research focuses on novel strategies to address resistance and further improve patient outcomes.