A randomized phase III trial of oral S-1 plus cisplatin versus docetaxel plus cisplatin in Japanese patients with advanced non-small-cell lung cancer: TCOG0701 CATS trial

Background: Platinum-based two-drug combination chemotherapy has been standard of care for patients with advanced nonsmall-cell lung cancer (NSCLC). The primary aim was to compare overall survival (OS) of patients with advanced NSCLC between the two chemotherapy regimens. Secondary end points included progression-free survival (PFS), response, safety, and quality of life (QoL). Patients and methods: Patients with previously untreated stage IIIB or IV NSCLC, an Eastern Cooperative Oncology Group performance status of 0-1 and adequate organ function were randomized to receive either oral S-1 80 mg/m²/day on days 1-21 plus cisplatin 60 mg/m² on day 8 every 4-5 weeks, or docetaxel 60 mg/m² on day 1 plus cisplatin 80 mg/m² on day 1 every 3-4 weeks, both up to six cycles. Results: A total of 608 patients from 66 sites in Japan were randomized to S-1 plus cisplatin (n = 303) or docetaxel plus cisplatin (n = 305). OS for oral S-1 plus cisplatin was noninferior to docetaxel plus cisplatin [median survival, 16.1 versus 17.1 months, respectively; hazard ratio = 1.013; 96.4% confidence interval (CI) 0.837-1.227]. Significantly higher febrile neutropenia (7.4% versus 1.0%), grade 3/4 neutropenia (73.4% versus 22.9%), grade 3/4 infection (14.5% versus 5.3%), and grade 1/2 alopecia (59.3% versus 12.3%) were observed in the docetaxel plus cisplatin than in the S-1 plus cisplatin. There were no differences found in PFS or response between the two arms. QoL data investigated by EORTC QLQ-C30 and LC-13 favored the S-1 plus cisplatin. Conclusion: Oral S-1 plus cisplatin is not inferior to docetaxel plus cisplatin and is better tolerated in Japanese patients with advanced NSCLC.