Afatinib as First-Line Treatment in Asian Patients with EGFR Mutation-Positive NSCLC: A Narrative Review of Real-World Evidence

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) are a standard of care in the first-line treatment of patients with EGFR mutation-positive metastatic non-small-cell lung cancer (NSCLC). EGFR mutations are relatively common in Asian patients with NSCLC, and there is an increasing number of studies supporting the effectiveness of the second-generation TKI afatinib in routine clinical practice in Asia. This article reviews these real-world studies investigating afatinib as first-line treatment for EGFR mutation-positive NSCLC in Asian patients. Evidence from real-world studies with afatinib in this patient population supports findings from randomized controlled trials (RCTs) showing that afatinib is associated with more favorable outcomes compared with the first-generation EGFR TKIs. The effectiveness of afatinib has also been shown in real-world studies in Asian patients with poor prognostic factors, who are often under-represented or excluded from RCTs, such as those with uncommon EGFR mutations, brain metastases, or poor performance status, and elderly patients. The tolerability profile of afatinib in the real-world setting reflects that seen in RCTs, with no new safety signals reported in real-world studies in Asian patients with EGFR mutation-positive NSCLC. Dose-modification strategies also seem to be effective in the real world, with results of the RealGido study, which included 44% Asian patients, confirming findings from prospective clinical trials showing that tolerability-guided afatinib dose modifications can reduce the incidence of adverse events without adversely affecting clinical outcomes. While further research, including clinical trial data, is needed, real-world data have also demonstrated the feasibility of sequential afatinib followed by the third-generation TKI osimertinib in T790M-positive EGFR mutation-positive patients, which showed longer overall survival. Together, these real-world results demonstrate the real-world clinical effectiveness of afatinib as first-line treatment for patients with EGFR mutation-positive NSCLC.