Randomized phase III trial of paclitaxel, etoposide, and carboplatin versus carboplatin, etoposide, and vincristine in patients with small-cell lung cancer

Background: Paclitaxel administered in combination with a topoisomerase-II inhibitor (such as etoposide) and carboplatin is an effective and safe first-line treatment for patients with small-cell lung cancer (SCLC). We conducted a randomized phase III multicenter trial to determine whether paclitaxel plus etoposide plus carboplatin improves the outcome of patients with primary SCLC relative to standard chemotherapy (carboplatin, etoposide, and vincristine). Methods: Between January 1998 and December 1999, 614 patients with SCLC stages I-IV were randomly assigned to the standard arm (309 patients) or the experimental arm (305 patients). Treatment courses were repeated every 21 days for a maximum of six courses. All patients were evaluated for response rate, survival, and toxicities every two courses. The primary endpoint was survival. Survival curves were estimated with the Kaplan-Meier method and compared using the log-rank test. All statistical tests were two-sided. Results: A total of 608 patients were evaluable for all endpoints (standard arm 307 patients, experimental arm 301 patients). The hazard ratio [HR] of death for patients receiving the standard treatment was statistically significantly higher than that for patients receiving the experimental treatment (HR = 1.22, 95% confidence interval [CI] = 1.03 to 1.45; P = .024). Progression-free survival was also statistically significantly shorter for patients in the standard arm relative to that of patients in the experimental arm (HR = 1.21, 95% CI = 1.03 to 1.42). There were no differences in the response rates (complete and partial combined) to the treatments (standard arm: 69.4%, 95% CI = 63.9% to 74.5%; experimental arm: 72.1%, 95% CI = 66.7% to 77.1%; difference = 2.7%, 95% CI = 4.5% to 9.9%). Rates of severe grade of anemia, leukocytopenia, neutropenia, and thrombocytopenia were lower in the experimental arm than in the standard arm. Conclusion: Patients with previously untreated SCLC who received paclitaxel, etoposide, and carboplatin showed improved overall and progression-free survival and less frequent hematologic toxicities than those who received the standard therapy.