Phase II study of Amrubicin monotherapy in elderly or poor-risk patients with extensive disease of small cell lung cancer

Background Previous study indicated that an optional anti-cancer drug for the treatment of small-cell lung cancer (SCLC) is amrubicin. However, no prospective studies have evaluated amrubicin in chemo-naive elderly or poor-risk patients with SCLC. Therefore, this study aimed to evaluate the efficacy of amrubicin as first-line chemotherapy for elderly or poor-risk patients with extensive-disease SCLC (ES-SCLC). Methods Patients with chemotherapy-naive ES-SCLC received multiple cycles of 40 mg/m² amrubicin for 3 consecutive days every 21 days. The primary endpoint was the overall response rate (ORR), and the secondary endpoints were progression-free survival (PFS), overall survival (OS), and safety. Results Between March 2011 and August 2015, 36 patients were enrolled in this study. Each patient received a median of four treatment cycles (range, 1–6 cycles). ORR was 52.8% [95% confidence interval (CI), 37–69%]. The median PFS and OS periods were 5.0 months (95% CI, 3.4–6.6 months) and 9.4 months (95% CI, 5.2–13.6 months), respectively. Neutropenia was the most common grade 3 or 4 adverse event (69.4%), with febrile neutropenia developing in 13.9% of patients. No treatment-related death occurred. At the time of starting second-line chemotherapy, 19 of 22 patients (86%) had significantly improved or maintained their performance status (PS) relative to their PS at the time of starting amrubicin monotherapy as first-line chemotherapy (P = 0.027). Conclusions The results of the present study suggest that amrubicin could be considered as a viable treatment option for chemotherapy-naive elderly or poor-risk patients with ES-SCLC (Clinical trial registration number: UMIN000011055 www.​clinicaltrials.​gov).