413P - South Korean real-world treatment patterns in patients with EGFRm NSCLC

Background

In Asia, ∼40% of patients (pts) with non-small cell lung cancer (NSCLC) are epidermal growth factor receptor-mutation (EGFRm) positive. T790M mutation occurs in ∼50% of pts who develop resistance to a first-/second-generation (1G/2G) EGFR-tyrosine kinase inhibitor (TKI). To investigate prevailing treatment patterns and T790M testing practices in pts with EGFRm locally advanced/metastatic NSCLC treated with first-line (1L) 1G/2G EGFR-TKI, real-world (RW) data were obtained from pts in South Korea.

Methods

Retrospective, non-interventional medical record review of pts with EGFRm NSCLC treated with 1L 1G/2G EGFR-TKIs in routine practice settings between 1 Jan 2015–31 Dec 2017 (follow up: end 2019). Study endpoints: demographic/disease characteristics, 1L EGFR-TKI therapy selection, T790M mutation testing and second-line (2L) therapy selection.

Results

235 pts were included: median age 70 (40–93) years, 63% female, and 64% never smoked. At initial NSCLC diagnosis, 89% of pts had metastatic disease, 63% had an ECOG PS score of 0/1; 57% were ex19del positive. 1L 1G/2G EGFR-TKI therapy: 45% afatinib; 43% gefitinib; 13% erlotinib. 164/235 pts (70%) progressed on 1L therapy; median treatment duration of 10.3 months (mo; range: 0.1–37.2). 71/235 pts (30%) did not progress: 37 (16%) remained on 1L therapy and 34 (14%) discontinued 1L therapy before end of follow-up. 22/235 (9%) died during/after 1L therapy without receiving 2L therapy. Following progression, 68% (n=111/164) were tested for T790M, 43% (n=48/111) were T790M positive; 88% (n=42/48) of those received osimertinib. Overall, 120/164 (73%) received 2L therapy – mainly pemetrexed (n=49; 41%).

Conclusions

In this study, of pts who progressed on 1L 1G/2G EGFR-TKI, 27% did not receive 2L therapy, while only 68% were T790M tested; 88% of positive pts received osimertinib. Suboptimal rates of mutation testing and use of recommended 2L therapies may reflect the fact osimertinib was not reimbursed in South Korea until Dec 2017.

Clinical trial identification

Editorial acknowledgement

Louise Prince, PhD of Ashfield Healthcare Communications, part of UDG Healthcare plc, who provided medical writing support funded by AstraZeneca, Cambridge, UK, the manufacturer of osimertinib, in accordance with Good Publications Practice (GPP3) guidelines.

Legal entity responsible for the study

AstraZeneca.

Funding

AstraZeneca.

Disclosure

Y-C. Kim: Honoraria (institution), Research grant/Funding (self): AstraZeneca; Honoraria (self), Research grant/Funding (self): Roche; Honoraria (self), Research grant/Funding (self): Boehringer Ingelheim. K. Davis: Research grant/Funding (institution), Full/Part-time employment, Employee of RTI Health Solutions, which has received contract research funding from AstraZeneca for my participation in the conduct of the currently submitted study/abstract: RTI Health Solutions; Research grant/Funding (self): Novartis; Research grant/Funding (self): Pfizer; Research grant/Funding (self): Vertex; Research grant/Funding (self): Eli Lilly; Research grant/Funding (self): Eisai. S.P. Nagar: Full/Part-time employment: RTI Health Solutions. W. Sawyer: Full/Part-time employment, I am an independent statistical contractor working for AstraZeneca. N. Yu: Full/Part-time employment: AstraZeneca. A. Taylor: Shareholder/Stockholder/Stock options, Full/Part-time employment: AstraZeneca. All other authors have declared no conflicts of interest.