As reported in the Journal of Clinical Oncology by Zhong et al, the final overall survival results of the phase III CTONG1104 trial indicated no significant advantage of adjuvant gefitinib vs vinorelbine/cisplatin in patients with EGFR-mutant stage II–IIIA (N1–2) non–small cell lung cancer (NSCLC).
The previously reported primary analysis showed that disease-free survival was significantly prolonged with gefitinib vs vinorelbine/cisplatin.
In the multicenter trial, 222 patients were randomly assigned between September 2011 and April 2014 to receive gefitinib for 24 months (n = 111) or vinorelbine/cisplatin every 3 weeks for four cycles (n = 111). The primary endpoint was disease-free survival. Overall survival was a secondary endpoint.
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The median follow-up was 80.0 months. Median overall survival was 75.5 months in the gefitinib group vs 62.8 months in the vinorelbine/cisplatin group, with the difference not being statistically significant (hazard ratio [HR] = 0.92, 95% confidence interval [CI] = 0.62–1.36, P = .674). Overall survival at 5 years was 53.2% vs 51.2% (P = .784).
After disease progression, subsequent therapy was received by 68.4% vs 73.6% of patients; of these, 38.6% vs 51.5% received targeted therapy. Median overall survival was 57.4 months vs 28.7 months for subsequent therapy vs no subsequent therapy in the gefitinib group and 51.9 months vs 15.6 months in the vinorelbine/cisplatin group.
Among all patients, median overall survival was 76.2 months in those receiving targeted therapy, 39.3 months in those receiving other subsequent therapy, and 23.4 months in those not receiving subsequent therapy. Subsequent targeted therapy contributed most to overall survival (HR = 0.23, 95% CI = 0.14–0.38) vs no subsequent therapy.
Updated 3- and 5-year disease-free survival rates in the gefitinib vs vinorelbine/cisplatin groups were 39.6% vs 32.5% (P = .316) and 22.6% vs 23.2% (P = .928).
The investigators concluded, “Adjuvant therapy with gefitinib in patients with early-stage NSCLC and [an] EGFR mutation demonstrated improved disease-free survival over standard-of-care chemotherapy. Although this disease-free survival advantage did not translate to a significant overall survival difference, overall survival with adjuvant gefitinib was one of the longest observed in this patient group compared with historic data.”
Yi-Long Wu, MD, of Guangdong Provincial People’s Hospital and Guangdong Academy of Medical Sciences, Guangzhou, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was funded by Guangdong Provincial Key Laboratory of Lung Cancer Translational Medicine, National Health and Family Planning Commission of People’s Republic of China, and AstraZeneca China. For full disclosures of the study authors, visit ascopubs.org.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.