Gemcitabine/Carboplatin in Patients with Metastatic Non-Small-Cell Lung Cancer: Phase II Study of 28-Day and 21-Day Schedules

BACKGROUND: The combination of gemcitabine/carboplatin is active and is widely used for advanced non-small-cell lung cancer (NSCLC). The optimum schedule for the administration of these agents is not currently known. This study compared 2 different combinations of carboplatin/gemcitabine to identify a schedule with a superior therapeutic index. PATIENTS AND METHODS: The 28-day schedule used gemcitabine 1100 mg/m2 on days 1 and 8 plus carboplatin to an area under the curve (AUC) of 5 on day 8. The 21-day schedule used gemcitabine 1000 mg/m2 on days 1 and 8 plus carboplatin to an AUC of 5 on day 1. RESULTS: Four hundred ninety-nine chemotherapy-naive patients with stage IIIB NSCLC (with malignant pleural effusion) or stage IV NSCLC were accrued. Grade 3/4 toxicities with the 28-day and 21-day schedules were anemia (4.8% and 6.9% of cycles, respectively), neutropenia (9.1% and 10.7% of cycles, respectively), and thrombocytopenia (8% and 14.4% of cycles, respectively). Thirty-four patients (13.2%) received blood transfusions with the 28-day regimen, as did 43 (20%) with the 21-day regimen, and no bleeding episodes occurred. Overall response rates were 22.8% with the 28-day schedule and 32.6% with the 21-day schedule (P = 0.0338). Median survival and 1-year and 2-year survival rates were 9.8 months, 38.6%, and 15.7%, respectively, with the 28-day schedule and 12 months, 49.1%, and 15.8%, respectively, with the 21-day schedule (P = 0.5098). CONCLUSION: Gemcitabine/carboplatin demonstrated efficacy comparable to other platinum agent doublets. Either schedule can be recommended, as differences in survival between groups were not significant.