Osimertinib in Patients With Lung Cancer Who Have Uncommon EGFR Mutations
Posted: Tuesday, March 10, 2020
Based on the results from a multicenter, single-arm, open-label, phase II trial, Jang Ho Cho, MD, of Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, and colleagues found that osimertinib was active in patients with non–small-cell lung cancer (NSCLC) harboring uncommon EGFR mutations. According to investigators, osimertinib was associated with a high response rate, an encouraging progression-free survival, and a long duration of response with manageable toxicity in this patient population. Their results were published in the Journal of Clinical Oncology.
In this trial, 36 evaluable patients with a histologically confirmed diagnosis of metastatic or recurrent NSCLC harboring EGFR mutations other than exon 19 deletion, L858R, T790M, or exon 20 insertion were included in safety and efficacy analyses. Investigators additionally performed a subset analysis by uncommon mutation type and found G719X (in 53% of patients), L861Q (in 25% of patients), and S768I (in 22% of patients) to be the most common rare mutations.
Approximately 60% of patients received osimertinib in the first-line setting.
At the time of data cutoff, the objective response rate and progression-free survival were 53% and 8.2 months, respectively, with a median follow-up duration of 20.6 months. In addition, the median duration of response was 11.2 months. Tumor shrinkage was observed in 28 patients. The median overall survival was not reached. Adverse events of any grade included rash, pruritus, decreased appetite, diarrhea, and dyspnea; all were reported to be manageable.
“Although a small number of patients were assessed, osmertinib can be considered as a treatment option for patients with NSCLC with uncommon EGFR mutations on the basis of this study,” proposed the authors.
Disclosure: The study authors’ disclosure can be found at ascopubs.org.