CHICAGO–The European Tarceva (erlotinib) versus Chemotherapy (EURTAC) study, the first prospective analysis of an EGFR tyrosine-kinase inhibitor vs. chemotherapy (CT) for the first-line treatment of patients with EGFR mutation-positive non-small cell lung cancer (NSCLC), met its primary endpoint of improved progression-free survival (PFS), demonstrating a 63% reduction in risk of progression or death, investigators reported at the American Society of Clinical Oncology’s 2011 Annual Meeting. Additionally, erlotinib had acceptable toxicity compared with platinum-based chemotherapy.

EGFR tyrosine kinase activating mutations are present in 10–26% of NSCLC tumors and are associated with increased response to gefitinib and erlotinib. However, little is known about how the efficacy and safety profile of erlotinib compares with CT in Caucasian patients with EGFR mutations.

Rafael Rosell, MD, PhD, from the Spanish Lung Cancer Group; Catalan Institute of Oncology, Barcelona, Spain, and colleagues, performed a prospective, randomized Phase 3 study comparing erlotinib 150mg/day with platinum-based CT in chemonaive patients with stage IIIb/IV NSCLC and EGFR mutations. From February 2007 to January 2011, the investigators screened 1,227 patients for EGFR mutations, and 174 patients with EGFR exon 19 deletion or exon 21 L858R mutation were randomly assigned to receive erlotinib or platinum-based CT. The primary endpoint was PFS and secondary endpoints included response, overall survival (OS) and toxicity profiles.

Of the 174 randomized patients, 153 (erlotinib [n=86], CT [n=87]) were evaluable for the updated analysis. Patient characteristics were comparable between the erlotinib and CT arms: males 33% vs. 22%, median age 65 years vs. 65 years, never smokers 66% vs. 67%, performance status (PS) 0 31% vs. 34%, PS 1 55% vs. 52%, and EGFR mutation type, exon 19 deletion, 66% vs. 67%, and L858R mutation, 34% vs. 33%, respectively.

Response rate was 15% in the CT arm vs. 58% in the erlotinib arm (P<0.0001), Dr. Rosell and colleagues reported; PFS was 5.2 months and 9.7 months, respectively (HR=0.37; P<0.0001). At an interim analysis, OS was 18.8 months in the CT arm and 22.9 months in the erlotinib arm (HR=0.80; P=0.42).

Dr. Rosell et al. conclude that erlotinib demonstrated better response rates and PFS in the EURTAC study.