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

Background

The EGFRm rate in metastatic NSCLC is 30%∼40% in China. Osimertinib, 3^rd generation EGFR-TKI, is approved as the 1^st 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 2^nd 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.

Methods

This 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.

Results

A 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 1^st line, 2^nd line, 3^rd line, and more than 3^rd 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 1^st line EGFR-TKI. For patients (N = 145) with T790M (+) metastatic NSCLC treated by Osimertinib as 2^nd 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 2^nd line Osimertinib, 78.9% received chemotherapy, 13.4% received bevacizumab combined with chemotherapy, and 7.7% received immunotherapy, respectively.

Conclusions

Osimertinib was generally used as 2^nd line treatment in patients who were resistance to the 1^st line EGFR-TKI in China. Real-word data further demonstrated and validated the similar efficacy of Osimertinib as 2^nd line therapy in China as that previously reported clinical trials.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.