Sorafenib in platinum-treated patients with extensive stage small cell lung cancer: a Southwest Oncology Group (SWOG...

Sorafenib is a multikinase inhibitor affecting pathways involved in tumor progression and angiogenesis. We conducted a phase II trial of sorafenib in platinum-treated patients with extensive stage small cell lung cancer to determine the tumor response rate, toxicity, and overall survival.

Patients with histologically confirmed, measurable disease, Zubrod performance status 0 to 1, and no more than 1 prior platinum-based treatment were eligible. Patients were stratified by platinum-sensitivity status: sensitive (progression >90 days after platinum) or refractory (progression during or ≤90 days after platinum). Patients were treated with sorafenib 400 mg orally twice a day continuously on a 28-day cycle.

Of 89 patients registered, 82 were evaluable for toxicity assessment, and 83 were evaluable for response. There were four partial responses seen among the 38 patients in the platinum-sensitive stratum, for an estimated response rate of 11% (95% confidence interval: 3-25%), and one partial response among the 45 patients in the platinum-refractory stratum, for an estimated response rate of 2% (95% confidence interval: 0-12%). The median overall survival estimates were 6.7 months (95% confidence interval: 6.1-9.1 months) for the platinum-sensitive stratum and 5.3 months (95% confidence interval: 3.3-7.5 months) in the platinum-refractory stratum. Nineteen patients discontinued treatment because of adverse events or side effects from therapy.

Based on the lack of disease control seen in our trial, further investigation of single-agent sorafenib in the small cell lung cancer population is not recommended. Combination trials of sorafenib and chemotherapy are ongoing.