Randomized Phase II Trial of Pemetrexed Combined With Either Cisplatin or Carboplatin in Untreated Extensive-Stage Small-Cell Lung Cancer

Abstract

Purpose: Given the activity and tolerability of pemetrexed/platinum combinations in non–small-cell lung cancer, and the success of novel therapeutic strategies employed in recent extensive-stage small-cell lung cancer (ES-SCLC) trials, a randomized phase II trial was initiated to evaluate the use of cisplatin or carboplatin plus pemetrexed in previously untreated ES-SCLC.Patients and Methods: Patients were randomly assigned to receive pemetrexed 500 mg/m²plus cisplatin 75 mg/m²or pemetrexed plus carboplatin area under the concentration curve 5. Treatment was administered once every 21 days for a maximum of six cycles. All patients received folic acid, vitamin B₁₂, and steroid prophylaxis.Results: Between December 19, 2002, and May 17, 2004, 78 patients were enrolled onto this multicenter trial. Median age was 63 years (range, 46 to 82 years) for cisplatin/pemetrexed and 66 years (range, 47 to 75 years) for carboplatin/pemetrexed. Median survival time (MST) for cisplatin/pemetrexed was 7.6 months, with a 1-year survivorship of 33.4% and a response rate of 35% (95% CI, 20.6% to 51.7%). The MST for carboplatin/pemetrexed was 10.4 months, with a 1-year survivorship of 39.0% and a response rate of 39.5% (95% CI, 24.0 to 56.6). Median time to progression for cisplatin/pemetrexed was 4.9 months and for carboplatin/pemetrexed was 4.5 months. Median dose-intensity (actual/planned dose) was 98.94% for cisplatin and 99.95% for pemetrexed in the cisplatin/pemetrexed group and 93.21% for carboplatin and 98.50% for pemetrexed in the carboplatin/pemetrexed group. Grade 3/4 hematologic toxicities included neutropenia (15.8% v 20.0%) and thrombocytopenia (13.2% v 22.9%) in the cisplatin/pemetrexed and carboplatin/pemetrexed treatment groups, respectively.Conclusion: Pemetrexed/platinum doublets had activity and appeared to be well-tolerated in first-line ES-SCLC.