A phase I dose-escalating study of combination S-1 and carboplatin (CBDCA) in patients with chemo-naïve advanced non-small cell lung cancer (NSCLC)
17055 Background: S1, a novel oral fluoropyrimidine derivative, has promising results in the treatment of advanced gastric or colorectal carcinoma. Response rate/median survival time of single S1 and the combination S1 plus cisplatin for advanced NSCLC were 22.0%/309 days and 47.3%/335 days, respectively in the previous phase II. Platinum doublets including a novel active drug is a potent standard for advanced NSCLC as 1st line chemotherapy. Carboplatin has advantage of low gastrointestinal or renal dysfunction in comparison with cisplatin. The primary objective of this study was to determine the maximum tolerated dose (MTD) of combination S-1 and carboplatin, the toxicity profile and the recommend dose (RD) for a multi-center randomized trial of platinum doublets including S1. Methods: Eligibility criteria includes histologically diagnosed NSCLC stage IIIB/IV, no prior chemotherapy, ECOG PS 0–1, 75 > age >20, adequate organ function, and written informed consent. Pts receive carboplatin intravenously over 30 minutes on day 1, and S1 daily for 2 weeks, every 3 weeks. Results: Total 10 patients were registered (M/F: 6/4; median age:67 (37–73); Ad/Sq:7/3; IIIB/IV: 0/10 PS 0/1:3/7) Three patients were enrolled at the dose level 1 (CBDCA AUC = 5 and S1 65 mg/m2), 3 patients at level 2 (CBDCA AUC=5 and S1 80 mg/m2) and 4 patients at level 3 (CBDCA AUC=6 and S1 80 mg/m2), respectively. No DLTs (dose-limiting toxicities) occurred at both level 1 and 2. DLTs were observed in 2 out of 4 patients at level 3. One is significant delay starting of 2nd cycle caused by thrombocytopenia. One is G3 anorexia and vomiting at 1st cycle and results in stop the treatment. A total 27 courses were assessable for safety. Two pts with G3 neutropenia, 2 pts with G3 anorexia, 1 pts with G3 liver dysfunction and 1 pts with G3 infection were observed during total courses. Five out of 6 patients at Level 1 or 2 have completion of 4 cycle’s treatment. Objective response was obtained in three patients out of 10. Conclusions: MTD was level 3. RD for the future trial was Level 2 (CBDCA AUC = 5 and S1 80 mg/m2). This combination was well tolerated and produced an antitumor effect for advanced NSCLC. No significant financial relationships to disclose.