A randomized, Open-Label, phase II study comparing pemetrexed plus cisplatin followed by maintenance pemetrexed versus pemetrexed alone in patients with epidermal growth factor receptor (EGFR)-Mutant non-small cell lung cancer after failure of First-Line EGFR tyrosine kinase inhibitor: KCSG-Lu12-13

Purpose The optimal cytotoxic regimens have not been established for patients with non-small cell lung cancer (NSCLC) who develop disease progression on first-line epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). Materials and Methods We conducted a multi-center randomized phase II trial to compare the clinical outcomes between pemetrexed plus cisplatin combination therapy followed by maintenance pemetrexed (PC) and pemetrexed monotherapy (P) after failure of first-line EGFR-TKI. The primary objective was progression-free survival (PFS), and secondary objectives included overall response rate (ORR), overall survival (OS), health-related quality of life (HRQOL), and safety and toxicity profiles. Results A total of 96 patients were randomized, and 91 patients were treated at 14 centers in Korea. The ORR was 34.8% (16/46) for the PC arm and 17.8% (8/45) for the P arm (p=0.066). With 23.4 months of follow-up, the median PFS was 5.4 months in the PC arm and 6.4 months in the P arm (p=0.114). The median OS was 17.9 months and 15.7 months in PC and P arms, respectively (p=0.787). Adverse events ≥ grade 3 were reported in 12 patients (26.1%) in the PC arm and nine patients (20.0%) in the P arm (p=0.491). The overall time trends of HRQOL were not significantly different between the two arms. Conclusion The outcomes of pemetrexed therapy in NSCLC patients with disease progression after first-line EGFR-TKI might not be improved by adding cisplatin.