RT Journal Article T1 Updated Overall Survival in a Randomized Study Comparing Dacomitinib with Gefitinib as First-Line Treatment in Patients with Advanced Non-Small-Cell Lung Cancer and EGFR-Activating Mutations. A1 Mok, Tony S A1 Cheng, Ying A1 Zhou, Xiangdong A1 Lee, Ki Hyeong A1 Nakagawa, Kazuhiko A1 Niho, Seiji A1 Chawla, Alka A1 Rosell, Rafael A1 Corral, Jesus A1 Migliorino, Maria Rita A1 Pluzanski, Adam A1 Noonan, Kay A1 Tang, Yiyun A1 Pastel, Malaika A1 Wilner, Keith D A1 Wu, Yi-Long AB ARCHER 1050, an ongoing, randomized, open-label, phase III trial of dacomitinib versus gefitinib in newly diagnosed patients with advanced non-small-cell lung cancer (NSCLC) and an EGFR-activating mutation, reported significant improvement in overall survival (OS) with dacomitinib. This paper reports an updated OS analysis of ARCHER 1050 after an extended follow-up. In this multinational, multicenter trial, adults (aged ≥ 18 years or ≥ 20 years in Japan and Korea) with newly diagnosed NSCLC and EGFR mutation (exon 19 deletion or exon 21 L858R substitution), and no history of central nervous system metastases, were randomized 1:1 to receive dacomitinib 45 mg/day (n = 227) or gefitinib 250 mg/day (n = 225). Randomization was stratified by race and EGFR mutation type. An ad hoc updated analysis of OS was conducted at the protocol-defined cut-off of 48 months from first dosing of the last enrolled patient (13 May 2019). After a median follow-up of 47.9 months, 133 (58.6%) patients had died in the dacomitinib arm and 152 (67.6%) in the gefitinib arm. The hazard ratio (HR) for OS was 0.748 (95% CI 0.591-0.947; two-sided P = 0.0155); median OS was 34.1 months with dacomitinib versus 27.0 months with gefitinib. The HR for OS in patients with dose reduction(s) in the dacomitinib arm (n = 154) compared with all patients in the gefitinib arm was 0.554 (95% CI 0.420-0.730); median OS was 42.5 months for patients with dose reduction(s) in the dacomitinib arm. The most common adverse events were diarrhea (87.7%), paronychia (61.7%), dermatitis acneiform (49.3%), and stomatitis (43.6%) with dacomitinib, and diarrhea (55.8%) and alanine aminotransferase increased (40.2%) with gefitinib. The OS benefit from first-line treatment with dacomitinib versus gefitinib was maintained after extended follow-up in patients with advanced NSCLC with EGFR-activating mutations. CLINICALTRIALS.GOV: NCT01774721 (registered 24 January 2013). YR 2021 FD 2021 LK http://hdl.handle.net/10668/16812 UL http://hdl.handle.net/10668/16812 LA en DS RISalud RD Apr 10, 2025