Phase II Study of Erlotinib in Japanese Patients with Pretreated EGFR Mutation Positive Non-Small Cell Lung Cancer: Lung Oncology Group in Kyushu, Japan (LOGIK0803)

Background Erlotinib has been reported to be useful for treating EGFR mutation-positive (EGFR-mt) non-small cell lung cancer (NSCLC) (OPTIMAL ESMO 2010, EURTAC Lancet Oncol. 2012). However, its usefulness had not been investigated in Japanese patients. Hence, we conducted a multicenter phase II study to investigate the efficacy and safety of erlotinib in Japanese patients with pretreated EGFR-mt NSCLC. Methods Erlotinib, 150 mg/day, was orally administered daily to patients with pretreated EGFR-mt (exon 19/21) NSCLC who had not been treated with EGFR-TKIs. The primary endpoint was objective response rate (ORR), and the secondary endpoints were disease control rate (DCR), progression-free survival (PFS), and safety. Results Between April 2009 and January 2011, 26 patients were enrolled from 15 participating centers. The patient characteristics were as follows: median age, 68 years (51 to 79); men/women, 11/15; adenocarcinoma/others, 24/2; nonsmoking/smoking, 20/6; ECOG PS 0/1/2, 16/8/2; exon 19/21, 19/7; and 2nd/3rd line therapy, 25/1. The antitumor effect was as follows: PR, 14 patients; SD, 7 patients; PD, 4 patients; NE, 1 patient; ORR, 54%; and DCR, 81%. The ORR and DCR according to the EGFR status were 47.4%/71.4% (exon 19/21, p = 0.3913) and 73.7%/100% (p = 0.2782), respectively. The PFS was 9.3 months (range, 0.9 to 19.2 mo). Major adverse drug reactions were rash (96%) and hepatic function disorder (40%); most episodes were grade 2 or less, and all were tolerable. No patients developed interstitial lung disease, and there were no treatment-related deaths. Conclusion In this study, the usefulness of erlotinib was investigated prospectively in Japanese patients with pretreated EGFR-mt NSCLC for the first time, and this drug was shown to be effective and tolerable. At this congress, we will report the study results including the ORR and PFS according to the patient characteristics. Disclosure Y. Nakanishi: From Chugai Pharmaceutical, I received 7500 Euro as honoraria on 2011, and 22000 Euro on 2010 and 70000 Euro on 2011 as research grant. Y. Ichinose: I have research funding with Chugai Pharmaceutical company. All other authors have declared no conflicts of interest.