ESMO Asia 2015: Afatinib a Better Choice for EGFR-Mutated Lung Cancer in First-Line Treatment
Patients with epidermal growth factor receptor (EGFR)-activating mutations in advanced lung cancer seem to benefit more from afatinib (Gilotrif) than gefitinib (Iressa) as first-line treatment, Park et al reported in a study (Abstract LBA2) presented at the European Society for Medical Oncology (ESMO) Asia 2015 Congress in Singapore.
In the global, randomized, open-label phase IIb LUX-Lung 7 trial, the irreversible ErbB family blocker afatinib significantly improved efficacy vs gefitinib across a range of clinically relevant endpoints, such as progression-free survival, time to treatment failure, and objective response rate. “Based on these results, I would consider afatinib as the EGFR tyrosine kinase inhibitor of choice for the first-line treatment for patients with EGFR mutation–positive non–small-cell lung cancer (NSCLC),” said Keunchil Park, MD, PhD, Head of the Division of Hematology/Oncology at Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
NSCLC is the most common type of lung cancer. Activating EGFR gene mutations are more frequently observed in nonsmokers and women and occur in 50% of Asians and only 10% of non-Asians. The targeted agents afatinib and gefitinib block key pathways involved in tumor growth and spread. They have both been approved for use in treatment-naive patients based on the results of phase III trials confirming their superiority compared to chemotherapy. Unlike the first-generation EGFR inhibitor gefitinib, the irreversible ErbB family blocker afatinib is suggested to be active in prolonging tumor response and delaying disease progression.
Study Findings
“First-line afatinib treatment significantly reduced the risk of lung cancer progression by 27% vs gefitinib,” Dr. Park said. “Interestingly, the improvement in progression-free survival became more pronounced over time with a significantly higher proportion of patients alive and progression-free at 18 months (27% vs 15%, P = .018) and 24 months (18% vs 8%, P = .018), showing a greater long-term benefit of using the irreversible ErbB family blocker afatinib.”
Out of the 319 patients who were randomly assigned to afatinib or gefitinib, a significantly higher proportion responded to the first than the second (70.0% vs 56.0%, P = .008) with a median duration of response of 10.1 months (95% confidence interval [CI] = 7.82–11.10) and 8.4 months (95% CI = 7.36–10.94), respectively.
Regarding the tolerability profile, Dr. Park said, “Overall, the frequency of severe adverse events was similar in both arms with slightly different toxicity profiles. The adverse events observed with both treatments were predictable and manageable, leading to an equally low rate of treatment discontinuation in both arms (6.3%).”
The primary analysis of overall survival data is planned in 2016 and will provide further responses.
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®.
