497P - Real-word efficacy of osimertinib in patients with metastatic EGFRm NSCLC: An interim analysis from a multi-center study in China

Abstract

BackgroundThe EGFRm rate in metastatic NSCLC is 30%∼40% in China. Osimertinib, 3rd generation EGFR-TKI, is approved as the 1st line treatment for patients with advanced EGFRm NSCLC and 2nd line treatment for patients with EGFR T790M positive advanced NSCLC globally, and only is approved as the 2nd line treatment in China by now. This study is to investigate the efficacy of Osimertinib in patients with metastatic EGFRm NSCLC in the real word clinical setting in China. MethodsThis multi-center study was conducted in 13 medical centers in China from April 2017 to May 2019 (Clinical trial ID: 1800019903). Patients with metastatic EGFRm NSCLC received by Osimertinib were enrolled into this study. All data were collected and analyzed on China Multi-center Lung Cancer Precision Medicine Registry RWE Box. ResultsA total of 346 patients with metastatic EGFRm NSCLC were enrolled in this study (female: 56.5%, male: 43.5%). 95.1% patients were adenocarcinoma, 2.3% patients were squamous carcinoma and 1.7% patients were adenosquamous carcinoma. The percentage of Osimertinib as 1st line, 2nd line, 3rd line, and more than 3rd line therapy was 10.4%, 55.8%, 21.4% and 12.6%, respectively. 42.5% patients were identified as the secondary T790M (+)after failure of the 1st line EGFR-TKI. For patients (N = 145) with T790M (+) metastatic NSCLC treated by Osimertinib as 2nd line therapy, the ORR was 75.1%, the mPFS was 276 days. Subgroup analysis showed that for those with both T790M (+) and CNS metastasis (N = 146), the mPFS was 280 days and CNS ORR was 67.2%. Interestingly, the CNS ORR was 34.4% for those with T790M (-) of CNS metastasis. In patients (N = 193) who had progressed after 2nd line Osimertinib, 78.9% received chemotherapy, 13.4% received bevacizumab combined with chemotherapy, and 7.7% received immunotherapy, respectively. ConclusionsOsimertinib was generally used as 2nd line treatment in patients who were resistance to the 1st line EGFR-TKI in China. Real-word data further demonstrated and validated the similar efficacy of Osimertinib as 2nd line therapy in China as that previously reported clinical trials. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.