Low-Dose Gefitinib Treatment for Patients with Advanced Non-small Cell Lung Cancer Harboring Sensitive Epidermal Growth Factor Receptor Mutations

Introduction: Although standard schedule of gefitinib was the administration of 250 mg tablet every day, many patients need dose reduction because of toxicities. However, the efficacy of such low-dose gefitinib for patients with epidermal growth factor receptor-mutated non-small cell lung cancer has rarely been evaluated. Methods: A post hoc comparison of the efficacy (response rate and survival) in patients treated with gefitinib with or without any dose reduction in NEJ002 study was performed. Results: Among 114 patients treated with first-line gefitinib in NEJ002, 61 (54%) continued gefitinib without any dose reduction until their diseases progressed, and 53 (46%) reduced their dose of gefitinib because of some toxicities. There was no significant difference of patient characteristics between the two groups. The progression-free survival of low-dose group tended to be better than that of standard-dose group (median progression-free survival, 11.8 versus 9.9 months; p = 0.144), and the overall survival of low-dose group was also better than that of standard-dose group (median survival time, 32.7 versus 25.3 months; p = 0.049). Conclusions: The results suggest that low-dose gefitinib may be clinically not inferior to standard-dose gefitinib for non-small cell lung cancer with sensitive epidermal growth factor receptor mutations. Prospective study of low-dose gefitinib is warranted especially for frail patients who need less toxic treatment.