Does EGFR Mutation Type Influence Patient-Reported Outcomes in Patients with Advanced EGFR Mutation-Positive Non-Small-Cell Lung Cancer? Analysis of Two Large, Phase III Studies Comparing Afatinib with Chemotherapy (LUX-Lung 3 and LUX-Lung 6)

In LUX-Lung 3 and LUX-Lung 6, afatinib significantly improved progression-free survival (PFS) versus chemotherapy in patients with tumors harboring common epidermal growth factor receptor (EGFR) mutations (Del19/L858R) and significantly improved overall survival (OS) in patients with tumors harboring Del19 mutations. Patient-reported outcomes stratified by EGFR mutation type are reported. Lung cancer symptoms and health-related quality of life (QoL) were assessed every 21 days until progression using the EORTC Quality of Life Core Questionnaire C30 and its lung cancer-specific module, LC13. Analyses of cough, dyspnea, and pain were prespecified and included analysis of percentage of patients who improved on therapy, time to deterioration of symptoms, and change over time. Global health status (GHS)/QoL was also assessed. Analyses were conducted for all patients with tumors harboring Del19 or L858R mutations and were exploratory. Compared with chemotherapy, afatinib more commonly improved symptoms of, delayed time to deterioration for, and was associated with better mean scores over time for cough and dyspnea in patients with Del19 or L858R mutations. All three prespecified analyses of pain showed a trend favoring afatinib over chemotherapy. In both Del19 and L858R mutations, afatinib was also associated with improvements in GHS/QoL. Longitudinal analyses demonstrated statistically significant improvements in GHS/QoL for afatinib over chemotherapy for patients with tumors harboring Del19 mutations or L858R mutations. These exploratory analyses suggest first-line afatinib improved lung cancer-related symptoms and GHS/QoL compared with chemotherapy in patients with non-small-cell lung cancer with tumors harboring common EGFR mutations, with benefits in both Del19 and L858R patients. When considered with OS (Del19 patients only) and PFS benefits, these findings substantiate the value of using afatinib over chemotherapy in these patient groups.