Phase II Study of S‐1 and Paclitaxel Combination Therapy in Patients with Previously Treated Non‐Small Cell Lung Cancer

LESSONS LEARNED: In terms of efficacy and safety, good results were obtained with S-1 and paclitaxel (PTX) combination therapy.The findings suggest that S-1 and PTX combination therapy is a feasible treatment option in patients with previously treated non-small cell lung cancer. BACKGROUND: Although monotherapy with cytotoxic agents, including docetaxel and pemetrexed, is recommended for patients with previously treated advanced non-small cell lung cancer (NSCLC), its outcomes are unsatisfactory. S-1 is an oral fluoropyrimidine agent that consists of tegafur, 5- chloro-2, 4-dihydroxypyridine, and potassium oxonate. S-1 is approved for patients with gastric cancer in 7 Asian countries and 15 European countries. It is also approved for patients with eight type of cancers, including NSCLC, in Japan. We evaluated the efficacy and toxicity of S-1 and paclitaxel (PTX) combination therapy in patients with previously treated NSCLC. METHODS: Oral S-1 was administered thrice weekly on days 1-14 at 80, 100, and 120 mg/day in patients with body surface areas of 1.5 m2, respectively. PTX was administered at 80 mg/m2 on days 1 and 8. Primary endpoint was response rate, and secondary endpoints were progression-free survival (PFS), overall survival (OS), and safety. RESULTS: Forty patients were enrolled, with response and disease control rates of 27.5% and 75.0%, respectively (Fig. 1). Median PFS and OS were 6.5 and 20.7 months, respectively. Grade 3/4 anemia and thrombocytopenia were seen in five (12%) and one (2%) patients, respectively. Febrile neutropenia occurred in three patients (7%). Common grade 3/4 nonhematological toxicities were stomatitis (5% of patients), diarrhea (7% of patients), and interstitial lung disease (one patient). No treatment-related deaths were observed. CONCLUSION: This S-1 and PTX cotherapy dose and schedule showed satisfactory efficacy, with mild toxicities, in patients with previously treated advanced NSCLC.