1292P - Phase II Trial of Afatinib as a Third-Line Treatment for Korean Patients (PTS) with Wild-Type Epidermal Growth Factor Receptor (WTEGFR) Stage IIIB/IV Lung Adenocarcinoma

Abstract

ABSTRACT Background EGFR inhibition benefits not only pts with mutated (mut) EGFR non-small cell lung cancer (NSCLC), but also pts with wtEGFR. Afatinib (BIBW 2992), an irreversible ErbB Family Blocker, has shown activity in heavily pretreated pts with mutEGFR NSCLC. This Phase II trial evaluated the efficacy of afatinib in pts with advanced wtEGFR NSCLC as third-line therapy at 3 Korean institutions. Methods Eligible pts had Stage IIIB/IV or recurrent wtEGFR (by local lab) lung adenocarcinoma with measurable disease, ECOG PS 0–2 and had failed 2 lines of chemotherapy (1–2 platinum-containing regimens). Prior treatment with anti-EGFR agents was not permitted. Pts received oral afatinib 40 mg/day until disease progression or occurrence of intolerable adverse events (AEs). The primary endpoint was confirmed objective tumour response rate (complete response [CR] + partial response [PR]) by RECIST 1.1; secondary endpoints included disease control rate (DCR = CR + PR + stable disease [SD]), progression-free survival (PFS), and safety profile. Results Forty-two pts received afatinib, but 4 pts were excluded from efficacy analyses because mutEGFR NSCLC was confirmed by central lab. Baseline pt characteristics were median age of 58.0 years, 79% male, 67% current/ex-smokers. Median treatment time with afatinib was 4.1 weeks (wks) (range 1.4–54.4 wks); 2 pts (1 pt with mutEGFR and 1 pt with wtEGFR) were still receiving afatinib at the time of analysis. No CRs or PRs were reported. DCR was 24% (9/38 pts) and the median duration of disease control was 19.3 wks (range 11.6–28.0 wks). Median PFS was 4.1 wks (95% CI: 3.9, 8.0). The most frequently reported AEs (mainly Grade 1 or 2) were rash (76%), diarrhoea (62%), and decreased appetite (43%). AEs led to dose reduction in 6 pts (14%) and discontinuation in 7 pts (17%). No treatment-related deaths were reported. Conclusions A proportion of heavily pretreated patients with wtEGFR NSCLC derived benefit from afatinib; further investigation will be planned including potential other biomarkers. Afatinib was tolerable as third-line treatment, with AEs that were manageable and consistent with the known safety profile. Disclosure B. Cho: Lecture fees from Merck and AstraZeneca; consulting fees from Merck. D. Massey: Employee of Boehringer-Ingelheim. M. Kim: Employee of Boehringer-Ingelheim. Y. Shi: Employee of Boehringer-Ingelheim. K. Park: Advisor/Consultant for AstraZeneca, Boehringer Ingelheim, Eli Lilly, Merck Sereno, Pfizer, Roche; Steering Committee for AMGEN, Kyowa Kirin. All other authors have declared no conflicts of interest.