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 <1.25, 1.25–1.5, and >1.5 m(2), respectively. PTX was administered at 80 mg/m(2) 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.