A Retrospective Study of Efficacy and Safety of Albumin-Bound Paclitaxel in Metastatic Breast Cancer

BACKGROUND: Nab-paclitaxel is a novel nanoparticle, albumin-bound, solvent-free, taxane-based chemotherapy approved for the treatment of metastatic breast cancer (MBC). This study reports clinical benefit and toxicities experienced by women with MBC treated with nab-paclitaxel. METHODS: Women with MBC treated with single-agent nab-paclitaxel between January 2012 and March 2014 were included in this analysis. Retrospective data obtained included demographics, disease characteristics, prior chemotherapy, nab-paclitaxel treatment, toxicity and survival. Clinical benefit was defined as partial or complete response or stable disease (by clinical or radiologic evaluation, or both) at 6 months or more. RESULTS: Overall response rates (complete or partial responses) were 43% (95% CI: 35.3 - 60.0) for all patients. Median time to disease progression was 26.6 weeks, and median survival was 63.6 weeks. No severe hypersensitivity reactions were reported despite the lack of premedication. Toxicities observed were typical of paclitaxel and included grade 3 sensory neuropathy (14.3%), grade 4 neutropenia (7.14%) and grade 4 febrile neutropenia (7.14%). Patients received a median of six treatment cycles; three patients had 25% dose reductions because of toxicities. CONCLUSIONS: Our clinical experience demonstrates that most women treated with nab-paclitaxel experienced some clinical benefit. Patients achieving clinical benefit lived significantly longer than those who did not. Nab-paclitaxel was well tolerated, with the primary toxicity being mild sensory neuropathy. Nab-paclitaxel represents another treatment option, with a favorable toxicity profile, for women with MBC.