Maintenance chemotherapy is a reasonable choice for patients with metastatic non-small cell lung carcinoma (NSCLC) not progressing after induction therapy with a platinum-based doublet. Nevertheless, there have been no studies dedicated to elderly patients.We conducted a randomised trial in patients aged 70-89 years, with advanced NSCLC (with neither EGFR mutation nor ALK rearrangement), who had not progressed after four cycles of monthly carboplatin and weekly paclitaxel in order to compare maintenance with either pemetrexed (500 mg/m2 d1, 22) in patients with non-squamous cell carcinoma or gemcitabine (1,150 mg/m2 d1, 8, 22) in squamous cell carcinoma to simple observation. The patients were required to have a performance status (PS) 0-2, mini-mental score >23, and creatinine clearance ≥45 mL/min. The primary end-point was overall survival (OS).632 patients were enrolled from May 2013 to October 2016. Of the 328 (52.3%) patients randomised after induction therapy, 166 patients were assigned to the observation arm, versus 162 to the switch maintenance arm, 119 of whom received pemetrexed and 43 gemcitabine. The median OS from randomisation was 14.1 months (95% confidence interval [CI]: 12.0-17.0) in the observation arm and 14 months (95% CI: 10.9-16.9) in the maintenance arm (p = 0.72). The median progression-free survival (PFS) from randomisation was 2.7 months (95% CI: 2.6-3.1) in the observation arm versus 5.7 months (95% CI: 4.8-7.1) in the maintenance arm (p < 0.001).Switch maintenance therapy significantly prolonged PFS but not OS and, thus, should not be proposed to elderly patients with advanced NSCLC.