Afatinib Versus Osimertinib as First-Line Treatment for Advanced EGFR-Mutant Non-Small-Cell Lung Cancer: A 3-Year Follow-Up Overall Survival Analysis

To date, there are limited clinical trials comparing the clinical efficacy between second-generation and third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKI)s.

The objective of this study was to compare the survival outcomes between afatinib and osimertinib as first-line treatments in patients with advanced EGFR-mutant non-small-cell lung cancer (NSCLC).

Between January 2018 and December 2020, we retrospectively enrolled patients with advanced NSCLC harboring an exon 19 deletion or L858R mutation who received afatinib or osimertinib as first-line treatment to analyze the progression-free survival (PFS) and overall survival (OS).

A total of 128 patients were included in this study, with 81 in the afatinib group and 47 in the osimertinib group. The median follow-up time was 39.9 months for the afatinib group and 37.0 months for the osimertinib group. The median PFS was 13.5 months in the afatinib group and 18.2 months in the osimertinib group (p = 0.240). The median OS was 40.5 months in the afatinib group and 37.0 months in the osimertinib group (p = 0.980). A total of 63% of patients received osimertinib as sequential therapy following progression on afatinib, with a median OS of 41.7 months. Among these patients, the median OS was 41.7 months for those with a detected T790M mutation, 42.0 months for those without the mutation, and 35.6 months for those with unknown T790M mutation status.

Our study demonstrated that both afatinib and osimertinib as first-line treatments offer favorable median OS in patients with advanced EGFR-mutant NSCLC. In addition, we recommend that patients receiving afatinib as first-line therapy undergo sequential osimertinib treatment, regardless of their T790M mutation status.