Phase II study of camtobell inj. (belotecan) in combination with cisplatin in patients with previously untreated, extensive stage small cell lung cancer

The aim of this study was to investigate the efficacy and safety of belotecan in combination with cisplatin in patients with previously non-treated extensive stage small cell lung cancer. A total of 42 patients were enrolled and treated with combination of belotecan 0.5 mg/m2 on daily basis throughout day 1-4 and cisplatin 60 mg/m2 on day 1 of a 3-week cycle, up to 6 cycles. Treatment was continued until the completion of 6 cycles of the chemotherapy, disease progression, detection of unacceptable toxicity, withdrawal of the consent, or death of the patient. Response was assessed every 2 cycles of chemotherapy by the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.0. Toxicity was assessed by the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE), version 3.0. The overall response rate was 73.8% in an intention to treat population and 83.9% in the evaluable patients. With the median follow up of 9.9 months, the median progression free survival was 6.9 months (95% CI, 6.6-7.2 months), and median overall survival was 11.2 months (95% CI, 9.9-12.5 months). The frequently reported grade ≥ 3 toxicities were neutropenia (90.2%), thrombocytopenia (63.4%), and anemia (34.1%). Febrile neutropenia was reported in 16 patients (39.0%). Although most of non-hematologic toxicities were grade 1 or 2, there were 4 patient deaths caused by pneumonia complicated by septic shock. Belotecan and cisplatin combination chemotherapy demonstrated a promising efficacy in ED SCLC patients. But, the hematologic toxicity of this regimen requires considerable amount of attention.