Phase II study of irinotecan and amrubicin in patients with relapsed non-small cell lung cancer: Okayama Lung Cancer Study Group Trial 0402

Background. The survival advantage achieved by existing anti-cancer agents as second-line therapy for relapsed non-small cell lung cancer (NSCLC) is modest and further improvement of treatment outcome is desired. Combination chemotherapy with irinotecan and amrubicin for advanced NSCLC has not been fully evaluated. Methods. The primary endpoint of this phase II clinical trial was objective response. Patients with NSCLC who had been treated previously with one or two chemotherapy agents were enrolled. Irinotecan and amrubicin were both administered on Days 1 and 8 of a 21-day cycle, at doses of 100 mg/m² and 40 mg/m², respectively. Results. Between 2004 and 2006, 31 patients received a total of 101 courses; the median number of courses administered was three (range, one to six). Objective response was obtained in nine of the 31 patients (29.0% response rate; 95% confidence interval (CI), 12.1-46.0%). With a median follow-up time of 43.9 months, median survival time and the median progression-free survival time were 14.2 and 4.0 months, respectively. Myelosuppression was the most frequently observed adverse event, with grade 3/4 neutropenia in 51% of patients. Febrile neutropenia developed after nine courses (9%) and resulted in one treatment-related death. Cardiac toxicity and diarrhea, possibly specific for both agents, were infrequent and manageable. Conclusion. Combination chemotherapy with irinotecan and amrubicin is effective in patients with NSCLC but showed moderate toxicities in second- or third-line settings.