Discussion
CNS METASTASES
This study aimed to assess the effectiveness and safety of second-line or higher osimertinib in a real-world setting in patients with The median PFS observed in our study was 11.7 months (95% CI 11.1–12.5), which was comparable with that reported in ASTRIS global population (Marinis et al. The effectiveness was also analyzed by the presence of CNS metastases. The benefit of osimertinib treatment was also found to be extended to the subgroup of Chinese Osimertinib was well-tolerated and no new safety signals were observed in our study. The safety profile was similar to that observed in the ASTIRS global population (Marinis et al. Although our study gives a better understanding of the effectiveness and safety aspects of osimertinib in a real-world scenario in a Chinese setting complementing the results of a global setting, certain limitations must be taken care of before drawing any conclusion. Considering the fact that due to many patients transitioning to commercial supply following national reimbursement as per ASTRIS protocol, the follow-up was incomplete and the exposure may have been underestimated. Also, the response rates were investigator-assessed as per institutional standards. Not all patients were assessed at baseline for the CNS metastases and the types of samples used and the availability of the type of testing methods for T790M at different study sites could also have introduced bias in the study results.