Role of nab-paclitaxel in metastatic breast cancer: a meta-analysis of randomized clinical trials

Whether nab-paclitaxel and conventional taxanes are equally effective for metastatic breast cancer (MBC) remains unclear. We conducted meta-analysis of trials that compared nab-paclitaxel-based chemotherapy with solvent-based paclitaxel (sb-paclitaxel) and docetaxel-based chemotherapy. A literature search was performed to identify articles that compared nab-paclitaxel-based chemotherapy with sb-paclitaxel or docetaxel-based chemotherapy for MBC. Four randomized controlled trials (1,506 patients) were identified from 1,268 reports. We detected equivalent overall response, overall survival, and survival probability (one-year, two-year). Grade 3 to 4 hematological and non-hematological toxicities were also comparable except that sensory neuropathy was more prominent for nab-paclitaxel-based chemotherapy (16.9% vs. 10%, odds ratio = 1.89, 95% confidence interval = 1.36-2.61, P < 0.001). No significant publication bias was detected. Consistent results stratified by treatment arm, study phase, treatment line, and study location were observed, except that overall response rate to nab-paclitaxel-based chemotherapy was significantly higher in the subgroup of randomized phase II trials, non-first-line treatment, and East Asian population. This meta-analysis failed to demonstrate advantages of nab-paclitaxel compared with sb-paclitaxel and docetaxel in patients with MBC. The newer agent was associated with increased sensory neuropathy, equivalent survival, and possibly increased overall response for some specific patients.