A phase II trial of Ifosfamide combination with recommended supportive therapy for recurrent SCLC in second-line and heavily treated setting

Purpose: The response rate of ifosfamide (IFM) monotherapy for small-cell lung cancer (SCLC) is reported as 42.4% in Japanese package insert. However, these efficacy data are based on clinical studies conducted in 1970s. This phase II study evaluated the efficacy and safety of IFM combination with recommended current supportive therapy for recurrent SCLC in second-line and heavily treated setting. Methods: Recurrent SCLC patients pretreated with one to three prior regimens received IFM monotherapy (1.5 g/m² for 3 days every 3 weeks). Treatment was continued until disease progression or unacceptable toxicity. The primary end point was objective response rate. Results: Twelve patients were enrolled in the study from June 2009 to January 2013. The study was early terminated at interim analysis due to futility stop. Patient characteristics were as follows: median age was 65 years, 11 were males (91.7%) and eight (66.7%) and four (33.3%) were Performance Status 0 and 1, respectively. Four patients (33.3%) enrolled in second-line setting were all refractory relapse SCLC and 8 (66.7%) were heavily treated patients. No patient showed objective response. Stable disease was observed in 3 patients. Median progression-free survival and overall survival were 0.9 months (95% CI, 0.3–1.5) and 4.8 months (95% CI, 1.6–9.9), respectively. Although one grade 4 amylase increase possibly related to IFM was observed, toxicity profile was totally favorable. Conclusions: IFM monotherapy should not be used for refractory relapse or heavily treated SCLC, and no further investigation is required in these populations.