Efficacy of Osimertinib Continuation Plus Metronomic Oral Vinorelbine for EGFRmutantAdvanced NSCLC Beyond Limited Progression on Osimertinib

Background: Treatment options for advanced non-small-cell lung cancer (NSCLC) after osimertinib failure are limited, and osimertinib continuation is recommended for selected patients. Metronomic oral vinorelbine is an effective treatment with less toxicity for advanced NSCLC. Objective: The objective of the study was to investigate the effects of osimertinib plus metronomic oral vinorelbine on epidermal growth factor receptor (EGFR)-mutant advanced NSCLC beyond limited progression on osimertinib. Methods: We have reviewed the medical records of 28 patients with EGFR-mutant advanced NSCLC who had received osimertinib continuation plus metronomic oral vinorelbine beyond limited progression on osimertinib. We also evaluated the clinicopathological characteristics of enrolled patients, as well as the efficacy and toxicity of the treatment Results: After a median follow-up period of 14.1 months, 57.1% (16/28) of cases showed NSCLC progression. The median progression-free survival (PFS) period under osimertinib plus metronomic oral vinorelbine was 9.4 months (95% confidence interval, 1.562–17.238 months), with a disease control rate of 89.3% and objective response rate of 17.9%. PFS did not differ between patients who had previously received osimertinib as first- (n = 16) and second-line (n = 12) therapy (median, 11.4 and 4.7 months, P = 0.391). In addition, the median PFS duration did not differ according to the efficacy (PFS2 ≥ 6 months vs. < months) of previous osimertinib monotherapy (median, 5.8 and 9.4 months, P = 0.677). Conclusions: Osimertinib continuation in conjunction with metronomic oral vinorelbine may enable overcoming TKI resistance and prolong the survival of patients with EGFR-mutant advanced NSCLC beyond limited progression on osimertinib treatment