Phase II trial of vinflunine in relapsed small cell lung cancer.

Background: Vinflunine is a new microtubule inhibitor with preclinical activity in small cell lung cancer (SCLC). In this phase II trial, we evaluated vinflunine in patients with relapse-sensitive and refractory SCLC.

Methods: This trial aimed to achieve a 20% objective response rate (ORR) in platinum-sensitive patients. Patients with Eastern Cooperative Oncology Group performance status 0 to 2 and measurable disease received vinflunine (320 mg/m(2) IV) every 21 days (< or =6 cycles; response evaluation every 6 weeks).

Results: Patient characteristics (N = 51): median age 63 years (range, 37-85 years); male, 55%; Eastern Cooperative Oncology Group performance status 2, 16%; relapse-sensitive SCLC, 53%. The overall ORR was 19.6% (95% confidence interval [CI] 10-33%). Twelve (23.5%) patients had stable disease; 18 (35.3%) patients had progressive disease. Among relapse-sensitive patients, ORR was 22.2% (95% CI 9-42%). Among relapse-refractory patients, ORR was 16.7% (95% CI 5-37%). Median follow-up was 15 months (range, 12-18 months); median progression-free survival (PFS) was 1.6 months (95% CI 1.3-3.9 months); median overall survival (OS) was 4.9 months (95% CI 3.2- 6.5 months). Among relapse-sensitive patients, PFS and OS were 1.6 and 4.9 months, respectively. Among relapsed-refractory patients, PFS and OS were 1.4 and 4.0 months, respectively. In general, vinflunine was well tolerated, although neutropenia was a notable toxicity. Grade 3/4 toxicities (>5%): neutropenia (32%), arthralgia/myalgia (16%), fatigue (16%), hyponatremia (12%), leukopenia (12%), nausea/vomiting (12%), constipation (6%), and thrombocytopenia (6%). The rates of toxicities were relatively well balanced among relapse-sensitive and refractory patients; one patient died of sepsis that was possibly treatment related.

Conclusions: Vinflunine has activity in relapsed SCLC, including refractory relapsed patients. Neutropenia was common but associated with rare febrile episodes. Additional study in relapse-refractory SCLC is indicated.