Phase II study of weekly amrubicin for refractory or relapsed small cell lung cancer

Background: Amrubicin hydrochloride is administered as second- or third-line therapy for small cell lung cancer, and is known to cause severe myelotoxicity. This study evaluated the efficacy and safety of weekly amrubicin for refractory/relapsed small cell lung cancer. Patients and Methods: A single-arm, open-label, multicenter, phase II study of weekly amrubicin was performed in 21 patients at seven centers in Japan from 2012 through 2015. Results: A partial response (PR) was noted in one out of the first 18 patients. The study was terminated early according to the termination criteria in the protocol. In total, the response rate was 19% (no complete responses and four PRs) and the disease control rate was 81% (17/21). Median overall survival was 288 days (95% confidence interval(CI)=208-424 days), while median progression-free survival was 113 days (95% CI=45-202 days). Conclusion: This study failed to demonstrate any efficacy of weekly amrubicin for refractory/relapsed small cell lung cancer.