Phase II trial of second-line bendamustine chemotherapy in relapsed small cell lung cancer patients

Summary 

Purpose

The efficacy and toxicity of bendamustine chemotherapy in relapsed small cell lung cancer (SCLC) was determined in this phase II trial.

Patients and Methods

Patients with cytologically or histologically proven SCLC, who had a sensitive relapse, which was defined as a relapse ≥2 months after completion of primary therapy, were eligible for this study. After informed consent patients received 120mg/m² of bendamustine on Days 1 and 2 every 3 weeks. A maximum of six cycles was administered. Primary endpoint was response rate, secondary endpoints included toxicity, progression free survival and overall survival (OS).

Results

Twenty-one patients with a median age of 59 years (range 47–76) were accrued to this trial. Six (29%) of 21 patients achieved a confirmed partial remission, 6 (29%) had stable disease and 9 (42%) patients progressed according to RECIST criteria. Median progression free survival was 4 months (95% CI 0–8, 3), median overall survival was 7 months (95% CI 5, 8–8, 2). One- and 2-year survival was 16% and 8%, respectively. Grade III/IV neutropenia occurred in 3 (15%) of 21 patients, 1 patient had a lethal Gram-negative sepsis in neutropenia. Two additional patients had pneumonia in the absence of neutropenia. Two patients (10%) had a grade III anemia, no grade III or IV thrombocytopenia was observed.

Conclusion

This trial demonstrates efficacy of bendamustine in relapsed SCLC and a favourable toxicity profile. Therefore, single-agent bendamustine is a treatment option for patients with SCLC, who have responded to initial platinum containing chemotherapy and should further be investigated in randomized trials.

Keywords: Relapsed SCLC, Bendamustine, Phase II study