A Phase Ii Study of Weekly Nanoparticle Albumin-Bound Paclitaxel Combined with Cisplatin in Patients with Metastatic Breast Cancer

e11568 Background: This prospective phase II study was to investigate the efficacy and toxicity of weekly albumin-bound paclitaxel (nab-paclitaxel) and cisplatin combination in patients with metastatic breast cancer. Methods: Females with unresectable, recurrent or metastatic breast cancer were eligible for participation. Nab-paclitaxel was administered weekly at a dose of 125 mg/m2 on d1, 8, 15, followed by cisplatin 75 mg/m2 on d1, repeated every 28 days with a maximum of 6 cycles. The primary objective was overall response rate (ORR) and the second objectives were progression free survival (PFS), safety, and overall survival (OS). Results: Seventy-three women were enrolled into this study. A total of 384 chemotherapy cycles were administered with a median of 6 cycles. A high overall response rate (67.1%) was achieved in the whole population. The highest response rate was observed in the first line patients (80.6%) and in patients who had not received taxane previously (80%). After a median follow-up of 12.8 months, the median PFS was 10.5 months. For the patients receiving first-, second- and third-line or more,median PFS was 12.3, 9.0 and 7.7 months, respectively (P=0.006). Subgroup analysis showed that the highest response rate was obtained in Her-2 positive patients, followed by patients with triple negative and luminal subtypes, yielding a response rate of 77.8%, 68.8% and 63.9%, respectively (P=0.584). The corresponding median PFS was 13.6, 12.7 and 10.0 months, respectively (P=0.83). While grade 4 neutropenia occurred in 46 patients (63.0%), febrile neutropenia occurred only in 9 patients (12.3%). Grade 3 peripheral neuropathy was an accumulated dose-limiting toxicity occurring in 19 patients (26.0%), 13 of whom had to stop chemotherapy due to no recovery to grade 2 or less within 2 weeks. Other common toxicities included alopecia, nausea, vomiting and rash. Conclusions: The results of this trial add to the clinical evidence that doublet of nab-paclitaxel and cisplatin has high efficacy and a good safety profile in treatment of patients with metastatic breast cancer. Further evaluation of this regimen in metastatic breast cancer, especially triple negative subtype, is justified.