A phase II study of S-1 for previously treated small cell lung cancer (SCLC)

Abstract

e19074 Background: S-1 is a novel oral 5-fluorouracil derivative that exhibits obvious activity against various tumor types including NSCLC. However, the effects of S-1 against SCLC have not been reported. The present phase II trial assesses the efficacy and safety of S-1 in previously treated SCLC patients. Methods: Eligible patients had pathologically documented SCLC that relapsed after platinum-based chemotherapy, ECOG performance status (PS) 0–2, and adequate bone marrow, kidney and liver function. Patients with untreated or symptomatic brain metastasis were excluded. Treatment comprised the oral administration of S-1 at 40 mg/m2 twice each day for 28 days every 6 weeks. The primary end point was the objective tumor response rate (RECIST). Secondary endpoints included progression-free survival and overall survival. Results: Twenty-six evaluable patients were enrolled (Simon's two-stage optimal design; α = 0.1; β = 0.1; P0 = 0.05; P1 = 0.25) with the following characteristics: male: female, 22/4; median age, 68 (33 - 79) y; PS0–1, n = 21; PS2, n = 5. The median number of prior treatment regimens was 2 (1–3). S-1 was administered for a mean of 1.3 cycles (1 - 5). One patient (3.8%) partially responded, 10 (38.5%) had stable and 15 (57.7%) had progressive disease. The overall response rate was 3.8% and the disease control rate was 42.3%. The median time to progression was 33 days. The median survival time was 8.0 months and the 1-year survival rate was 23%. This regimen was well tolerated. The common grade 3/4 toxicities included neutropenia (7.7%), leukopenia (7.7%), anemia (7.7%), hyponatremia (7.7%), rush (7.7%), infection (7.7%), and diarrhea (3.8%). None of the patients developed febrile neutropenia and no deaths were attributed to treatment. Conclusions: S-1 is well tolerated but has low activity as a single agent in previously treated patients with SCLC. No significant financial relationships to disclose.