Randomized phase II study of gefitinib versus erlotinib in patients with advanced non-small cell lung cancer who failed previous chemotherapy.

PURPOSE: Gefitinib and erlotinib are potent EGFR TKIs, with antitumor activity. In this randomized, single-center, non-comparative phase II trial, the efficacy and safety of gefitinib and erlotinib was evaluated as the second-line therapy for advanced non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS: Patients with locally advanced, metastatic stage IIIB/IV NSCLC who failed first-line chemotherapy and had either EGFR mutation or at least two out of three clinical factors associated with higher incidence of EGFR mutations (female, adenocarcinoma histology, and never-smoker) were eligible.

RESULTS: A total of 96 (48 per arm) patients were randomly assigned to gefitinib- or erlotinib-arm, respectively. Baseline characteristics were well-balanced between the two arms. The response rates (RR) were 47.9% in the gefitinib arm and 39.6% in the erlotinib arm. Median PFS was 4.9 months (95% CI, 1.3-8.5) in the gefitinib arm and 3.1 months (95% CI, 0.0-6.4) in the erlotinib arm. The most common grade 3/4 toxicity was skin rash. Exploratory analyses showed that there was no significant difference in RR and PFS in the gefitinib arm compared to the erlotinib arm (RR (%) 47.9 vs. 39.6, p=0.269; median survival (months) 4.9 vs. 3.1, p=0.336). There was no significant difference in QOL between the two arms.

CONCLUSION: Both gefitinib and erlotinib showed effective activity and tolerable toxicity profiles as second-line treatment for the selected population of NSCLC. We may consider conducting a phase III trial to directly compare the efficacy and toxicity between gefitinib and erlotinib in an enriched patient population.