A real-world study of dacomitinib in later-line settings for advanced non-small cell lung cancer patients harboring EGFR mutations.

Objective: Dacomitinib has been approved for the first-line treatment of non-small cell lung cancer (NSCLC) carrying classical epidermal growth factor receptor (EGFR) mutations; however, real-world data on its later-line application are lacking.

Materials And Methods: Patients' data were retrospectively collected from the Chinese National Cancer Center and the PLA hospital between August 2019 and August 2021. Kaplan-Meier method and Log-rank test were utilized to assess progression-free survival (PFS) and overall survival (OS). Univariate and multivariate Cox regression analysis was conducted to determine prognostic indicators.

Results: In total, 56 NSCLC patients harboring EGFR mutations treated with later-line single dacomitinib or combinatory dacomitinib were enrolled. A total of 53 patients (94.6%) had treatment-related adverse events; eight patients (14.3%) had grade 3 or 4 events. Among 49 evaluable patients, 26.5% (13 patients) had a confirmed partial response and 73.5% (36 patients) had disease control; the median duration of follow-up was 9.6 months (95% confidence interval [CI], 8.4-10.8 months), the median progression-free survival was 5.4 months (95% CI, 3.5-7.3 months), and the half-year, 1-year, and 2-year OS rate were 79.2%, 70.6%, and 64.1%, respectively. Univariate analysis suggested that smoking, line of dacomitinib, and interval between last EGFR-tyrosine kinase inhibitor (TKI) and dacomitinib were associated with PFS and OS; chemotherapy between last EGFR-TKI and dacomitinib, and EGFR-TKI generation followed by dacomitinib were respectively associated with PFS and OS; multivariate analysis indicated chemotherapy between last EGFR-TKI and dacomitinib negatively affect PFS, and smoking and third-generation EGFR-TKI followed by dacomitinib negatively affect OS.

Conclusions: This real-world study has shown that dacomitinib is active and well-tolerated in NSCLC patients harboring different EGFR mutations in later-line settings, even for those with brain metastases. Patients who benefited more from the first TKI were more likely to benefit from dacomitinib, and earlier application of dacomitinib after front-line TKI resistance may be considered.