Purpose: Platinum-based chemotherapy currently represents standard treatment for advanced non-small-cell lung cancer. Gemcitabine is one of the most interesting agents currently in use in advanced non-small-cell lung cancer, and high response rates have been reported when it is administered in combination with cisplatin. The aim of the present study was to evaluate the combination of gemcitabine and carboplatin in a phase I-II study.
Patients and methods: Chemotherapy-naive patients with stage IIIB-IV non-small-cell lung cancer received carboplatin at area under the concentration-time curve (AUC) 5 mg/mL/min and gemcitabine at an initial dose of 800 mg/m2, subsequently escalated by 100 mg/m2 per step. Gemcitabine was administered on days 1 and 8 and carboplatin on day 8 of the 28-day cycle. Dose escalation proceeded up to dose-limiting toxicity (DLT), which was defined as grade 4 neutropenia or thrombocytopenia or grade 3 nonhematologic toxicity.
Results: Neutropenia was DLT, inasmuch as it occurred in three of five patients receiving gemcitabine 1,200 mg/m2. Nonhematologic toxicities were mild. Gemcitabine 1,100 mg/m2 plus carboplatin AUC 5 was recommended for phase II studies. An objective response was observed in 13 (50%) of 26 patients, including four complete responses (15%) and nine partial responses (35%). Median duration of response was 13 months (range, 3 to 23 months). Median overall survival was 16 months (range, 3 to 26 months).
Conclusion: The combination of gemcitabine and carboplatin is well tolerated and active. Neutropenia was DLT. The observed activity matches that observable in cisplatin-gemcitabine studies, whereas duration of response and survival are even higher. A phase II trial is under way.