Objective: This analysis of the first-line cohort of LASER201 study evaluated the efficacy and safety of lazertinib 240 mg as a frontline therapy for epidermal growth factor receptor (EGFR)-mutated locally advanced or metastatic non-small cell lung cancer (NSCLC)., Methods: A total of 43 patients, with EGFR mutation-positive (Exon19Del, n = 24; L858R, n = 18; G719X, n = 1) locally advanced or metastatic NSCLC who had not previously received EGFR tyrosine kinase inhibitor (EGFR TKI) therapy, received once-daily lazertinib 240 mg. EGFR mutation status was confirmed by local or central testing. The primary endpoint was objective response rate (ORR) assessed by blinded independent central review. Secondary efficacy endpoints included duration of response (DoR), disease control rate (DCR), progression-free survival (PFS), tumor shrinkage, and overall survival (OS)., Results: At the primary data cut-off (DCO; January 8, 2021), the ORR was 70 % (95 % confidence interval [CI]: 56.0-83.5), DCR was 86 % (95 % CI: 75.7-96.4) and the median DoR was 23.5 (95 % CI: 12.5-not reached) months. The median PFS was 24.6 (95 % CI: 12.2-30.2) months. At the final DCO (March 30, 2023), the median OS was not estimable and the median follow-up duration for OS was 55.2 [95 % CI: 22.8-55.7] months. OS rates at 36 months and 54 months were 66 % (95 % CI: 47.5-79.3 %) and 55 % (95 % CI: 36.6-70.7 %), respectively. The most commonly reported TEAEs were rash (54 %), diarrhea (47 %), pruritus (35 %), and paresthesia (35 %). No drug-related rash or pruritus TEAEs of grade 3 or higher were reported. Diarrhea and paresthesia of grade 3 or higher were reported in 3 (7 %) and 1 (2 %) patients, respectively., Conclusion: This analysis demonstrated long-term clinical benefit with lazertinib 240 mg in patients with EGFR-mutated NSCLC who had not previously received EGFR TKIs. The safety profile for lazertinib was tolerable and consistent with that previously reported., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Byoung Chul Cho has received research funding from MOGAM Institute, LG Chem, Oscotec Inc., Interpark Bio Convergence Corp, GI Innovation, GI Cell, Abion, Abbvie, AstraZeneca, Bayer, Blueprint Medicines, Boehringer Ingelheim, Champions Oncology, CJ Bioscience, CJ Blossom Park, Cyrus, Dizal Pharma, Genexine, Janssen, Eli Lilly, MSD, Novartis, Nuvalent, Oncternal, Ono, Regeneron, Dong-A ST, BridgeBio Therapeutics, Yuhan Corporation, ImmuneOncia, Illumina, Kanaph Therapeutics, Therapex, JINTSbio, Hanmi, CHA Bundang Medical Center and Vertical Bio AG. He has received consulting fees from Abion, BeiGene, Novartis, AstraZeneca, Boehringer Ingelheim, Roche, BMS, CJ, CureLogen, Cyrus Therapeutics, Ono Pharmaceutical, Onegene Biotechnology, Yuhan Corporation, Pfizer, Eli Lilly, GI Cell, Guardant Health, HK Inno-N, Imnewrun Biosciences Inc., Janssen, Takeda, MSD, Janssen, Medpacto, Blueprint Medicines, RandBio, and Hanmi. He receives royalty from Champions Oncology, Crown Bioscience, Imagen and serves on the advisory board of Kanaph Therapeutics Inc., BridgeBio Therapeutics, Cyrus Therapeutics, Guardant Health, and Oscotech Inc, J INTS BIO, Therapex, Gilead, Amgen. He was an invited speaker for ASCO, AstraZeneca, Guardant Health, Roche, ESMO, IASLC, Korean Cancer Association, Korean Society of Medical Oncology, Korean Society of Thyroid-Head and Neck Surgery, Korean Cancer Study Group, Novartis, MSD, The Chinese Thoracic Oncology Society, and Pfizer. He is on the board of directors for J INTS BIO. He is an employee of Yonsei University Health System and the founder of the DAAN Biotherapeutics. He owns stocks of TheraCanVac Inc., Gencurix Inc., BridgeBio Therapeutics, Kanaph Therapeutics Inc., Cyrus Therapeutics, Interpark Bio Convergence Corp., and J INTS BIO. Ji-Youn Han reports research funding from Pfizer, Takeda, ONO, Roche; consulting fees from AstraZeneca, Janssen, Amgen, Oncobix, Merck, Novartis, Abion, Takeda, J INTS BIO and honoraria for lectures from AstraZeneca, Janssen, Takeda, Merck, Yuhan Corporation, Novartis and Pfizer and payment for expert testimony from AstraZeneca He participated in Data Safety Monitoring Board for AstraZeneca, Janssen, J INTS BIO. Ki Hyeong Lee reports grants from Merck Serono. He has received consulting fees from MSD, Pfizer, Eli Lilly, Yuhan Corporation, AstraZeneca, BMS. Yun-Gyoo Lee reports honoraria for lectures from AstraZeneca, MSD, Lilly, Boehringer Ingelheim and Yuhan. He participated in Data Safety Monitoring Board or Advisory Board for BeiGene, Dakeda, Guardant Health, Yuhan, Ono and Novartis. Dong-Wan Kim reports research funding to his institution from Alpha Biopharma, Amgen, AstraZeneca/Medimmune, Boehringer Ingelheim, BMS, BridgeBio Therapeutics, Chong Keun Dang, Daiichi-Sankyo, GSK, Hanmi, InnoN, Janssen, Merck, Merus, Mirati Therapeutics, MSD, Novartis, Ono Pharmaceutical, Pfizer, Roche/Genentech, Takeda, TP Therapeutics, Xcovery and Yuhan Corporation, and honoraria from the Korean Association for Lung Cancer, Korean Cancer Association, Korean Society of Medical Oncology, Taiwan Lung Cancer Society, Asian Thoracic Oncology Research Group. He reports travel support for attending meetings for the International Association for the Study of Lung Cancer, Asian Thoracic Oncology Research Group, Taiwan Lung Cancer Society. He provides medical writing assistance to Amgen, AstraZeneca, Boehringer-Ingelheim, BridgeBio Therapeutics, BMS, Chong Keun Dang, Daiichi-Sankyo, GSK, Pfizer, MSD, Merck, Merus, Novartis, Roche, Takeda, Yuhan Corporation. He participated in advisory boards for Amgen, AstraZeneca, BMS/Ono Pharmaceutical, Daiichi-Sankyo, GSK, Janssen, Meck, MSD, Pfizer, SK Biopharm, Takeda. He is on the Board of Directors for Asian Thoracic Oncology Research Group, Korean Association for Lung Cancer, Korean Cancer Association, and Korean Society of Medical Oncology. He is a scientific advisor for Health Insurance Review and Assessment Service, Republic of Korea. Eun Kyung Cho reports participation in data safety monitoring meeting for Yuhan Corporation for this clinical trial and received study drugs for conducting this clinical trial from Yuhan Corporation. Young Joo Min reports research funding from AstraZeneca, MSD, Merck, Ono Pharmaceutical, Yuhan Corporation, Amgen, Roche and honoraria from AstraZeneca, MSD, Merck, and Ono Pharmaceutical. Na Mi Lee, Jangyoung Wang, and Hyejoo Park are employees of Yuhan Corporation. Myung-Ju Ahn received consulting fees and research funding from AstraZeneca, Eli Lilly, MSD, Merck, Ono Pharmaceutical, Takeda, Yuhan Corporation, Amgen, Novartis, Roche, Alpha-Pharmaceuticals, and honoraria from AstraZeneca, Eli Lilly, MSD, Merck, Ono Pharmaceutical, Takeda, Yuhan Corporation, Amgen, Novartis and Roche. All other authors have no relevant relationships to disclose., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)