A Phase IIb, Randomized, Open, Parallel-Group, Multi-Center Trial to Assess the Efficacy and Safety of Belotecan(CamtoBell Inj.) or Topotecan in Patients With Relapsed Small Cell Lung Cancer

⁃ At least 18 years of age

⁃ Histological or cytological diagnosis of SCLC

⁃ Limited disease (LD) or Extensive disease (ED) at time of study entry

⁃ Recurrent or progressive SCLC ≥ 90 days of duration of response for firstline therapy

⁃ Measurable disease defined by RECIST criteria

⁃ ECOG Performance Status of 0, 1, or 2

⁃ Life expectancy ≥ 3 months

⁃ Adequate bone marrow, Renal, Hepatic reserve:

⁃ absolute neutrophil (segmented and bands) count (ANC) ≥ 1500 cells/mm3 platelet count ≥ 100,000 cells/ mm3 hemoglobin ≥ 9 g/dL Total bilirubin ≤ 1.5 mm3 Alanine aminotransferase (ALT) and aspartate aminotransferase(AST) ≤ 2.0 X ULN Alkaline Phosphatase (ALP) ≤ 2.0 X ULN Serum creatinine ≤ 1.5mg/dL or calculated creatinine clearance > 60mL/min

• Signed a written informed consent