Gefitinib or Erlotinib vs Chemotherapy for EGFR Mutation-Positive Lung Cancer: Individual Patient Data Meta-Analysis of Overall Survival

• Main Authors: Lee C., Davies L., Wu Y., Mitsudomi T., Inoue A., Rosell R., Zhou C., Nakagawa K., Thongprasert S., Fukuoka M., Lord S., Marschner I., Tu Y., Gralla R., Gebski V., Mok T., Yang J.
• Format: Journal
• Published: 2017
• Online Access: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85027265241&origin=inward; http://cmuir.cmu.ac.th/jspui/handle/6653943832/40447
• Institution: Chiang Mai University

Background: We performed an individual patient data meta-analysis to examine the impact of first-generation epidermal growth factor receptor ( EGFR ) tyrosine kinase inhibitor (TKI) therapy on overall survival (OS) in advanced non-small cell lung cancer (NSCLC). Methods: Data from trials comparing EGFR-TKI against chemotherapy in exon 19 deletion (del19) or exon 21 L858R (L858R) EGFR mutations patients were used. We performed Cox regression to obtain hazard ratios (HRs) and 95% confidence intervals (CIs). Impact of postprogression therapies was examined in exploratory analyses. All statistical tests were two-sided. Results: Six eligible trials (gefitinib = 3, erlotinib = 3) included 1231 patients; 632 received EGFR-TKI and 599 received chemotherapy. At a median 35.0 months follow-up, there were 780 deaths and 1004 progressions. There was no difference in OS between EGFR-TKI and chemotherapy (HR = 1.01, 95% CI = 0.88 to 1.17, P = .84). There was also no difference in OS for Del19 (n = 682, HR = 0.96, 95% CI = 0.79 to 1.16, P = .68) and L858R (n = 540, HR = 1.06, 95% CI = 0.86 to 1.32, P = .59) subgroups ( P interaction = .47), or according to smoking status, sex, performance status, age, ethnicity, or histology. However, EGFR-TKI statistically significantly prolonged progression-free survival (PFS) overall (HR = 0.37, 95% CI = 0.32 to 0.42, P < .001) and in all subgroups. Following progression, 73.8% from the chemotherapy arm received EGFR-TKI, and 65.9% from the EGFR-TKI arm received chemotherapy. Nine percent from the EGFR-TKI arm received no further treatment vs 0.6% from the chemotherapy arm. Following disease progression, patients randomly assigned to EGFR-TKI had shorter OS than those randomly assigned to chemotherapy (12.8 months, 95% CI = 11.4 to 14.3, vs 19.8 months, 95% CI = 17.6 to 21.7). Conclusions: Despite statistically significant PFS benefit, there is no relative OS advantage with frontline gefitinib or erlotinib vs chemotherapy in EGFR -mutated NSCLC. This finding is likely due to the high rate of crossover at progression.