Randomized Phase III Trial of Amrubicin Versus Topotecan As Second-Line Treatment for Patients With Small-Cell Lung Cancer

Purpose Amrubicin, a third-generation anthracycline and potent topoisomerase II inhibitor, showed promising activity in small-cell lung cancer (SCLC) in phase II trials. This phase III trial compared the safety and efficacy of amrubicin versus topotecan as second-line treatment for SCLC. Patients and Methods A total of 637 patients with refractory or sensitive SCLC were randomly assigned at a ratio of 2:1 to 21-day cycles of amrubicin 40 mg/m(2) intravenously (IV) on days 1 to 3 or topotecan 1.5 mg/m(2) IV on days 1 to 5. Primary end point was overall survival (OS); secondary end points included overall response rate (ORR), progression-free survival (PFS), and safety. Results Median OS was 7.5 months with amrubicin versus 7.8 months with topotecan (hazard ratio [HR], 0.880; P = .170); in refractory patients, median OS was 6.2 and 5.7 months, respectively (HR, 0.77; P = .047). Median PFS was 4.1 months with amrubicin and 3.5 months with topotecan (HR, 0.802; P = .018). ORR was 31.1% with amrubicin and 16.9% with topotecan (odds ratio, 2.223; P < .001). Grade >= 3 treatment-emergent adverse events in the amrubicin and topotecan arms were: neutropenia (41% v 54%; P = .004), thrombocytopenia (21% v 54%; P < .001), anemia (16% v 31%; P < .001), infections (16% v 10%; P = .043), febrile neutropenia (10% v 3%; P = .003), and cardiac disorders (5% v 5%; P = .759); transfusion rates were 32% and 53% (P < .001), respectively. NQO1 polymorphisms did not influence safety outcomes. Conclusion Amrubicin did not improve survival when compared with topotecan in the second-line treatment of patients with SCLC. OS did not differ significantly between treatment groups, although an improvement in OS was noted in patients with refractory disease treated with amrubicin. (C) 2014 by American Society of Clinical Oncology