A multicenter phase II study of belotecan, a new camptothecin analogue, in elderly patients with previously untreated, extensive-stage small cell lung cancer

Purpose Belotecan is a new camptothecin analogue and a potent topoisomerase I inhibitor. The aim of this phase II study was to investigate the efficacy and toxicity of belotecan in previously untreated elderly patients with small cell lung cancer (SCLC). Methods A total of 26 patients, aged ≥65 years, with previously untreated, extensive-stage SCLC were enrolled in the study. Belotecan was administered by daily intravenous infusion at 0.5 mg/m 2 /day for 5 consecutive days every 3 weeks. Results The overall response rate and disease control rate of chemotherapy on an intention-to-treat basis were 35 and 54 %, respectively. The median overall survival was 6.4 months, and the median time to progression was 2.8 months. The most common toxicity was hematologic. Grade 3 or 4 neutropenia occurred in 80.8 % of patients, and grade 3 or 4 thrombocytopenia in 15.3 %. Non-hematologic toxic effects of grade 3 or 4 were uncommon. Conclusion Belotecan had modest efficacy and well-tolerated toxicity in previously untreated, elderly SCLC patients. Single belotecan could be a promising treatment option, considering its lower toxicity in elderly patients who are unsuitable candidates for platinum plus etoposide chemotherapy.