Efficacy and Safety of S-1 Compared With Docetaxel in Elderly Patients With Advanced NSCLC Previously Treated With Platinum-Based Chemotherapy: A Subgroup Analysis of the EAST-LC Trial

Introduction: Despite recent advances in NSCLC treatment, specific data on the elderly population remain limited. In this post hoc subgroup analysis of the East Asia S-1 Trial in Lung Cancer (EAST-LC) trial, we compared S-1 and docetaxel (DTX) in patients aged 70 years old and above with pretreated advanced NSCLC. Methods: Patients were randomly assigned (1:1) to receive S-1 (orally, twice daily on d 1–28 of a 6-wk cycle) or DTX (intravenously, on d 1 of a 3-wk cycle). The initial S-1 dose was 80, 100, or 120 mg/day on the basis of body surface area, and the DTX doses were 60 mg/m2 (Japan) or 75 mg/m2 (outside Japan). The primary end point was overall survival, and secondary end points included progression-free survival, response rate, quality of life (QOL) using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core-30, and safety. Results: Among 189 patients aged 70 years and above assessed as the full analysis set, baseline characteristics were generally similar between treatment arms. The median overall survival was 14.7 (S-1) versus 12.1 months (DTX); the hazard ratio was equal to 0.76, with a 95% confidence interval (CI) of 0.54–1.07. The median progression-free survival was similar in both arms (both 4.1 mo, hazard ratio = 0.84, 95% CI: 0.60–1.18); and the response rate was 12.9% (S-1) and 14.0% (DTX). The adjusted mean QOL score difference (S-1–DTX until wk 48) was 7.41 (95% CI: 0.37–14.46). Safety profiles were generally consistent with those of the overall EAST-LC population. Conclusions: S-1 revealed comparable efficacy, safety, and QOL versus DTX in pretreated elderly patients with advanced NSCLC. Results were consistent with the overall EAST-LC data.