nab-Paclitaxel dose and schedule in breast cancer

Miguel Martín

nab-Paclitaxel is approved for the treatment of metastatic breast cancer on an every-3-week schedule based on positive findings from a pivotal phase III trial in which nab-paclitaxel 260 mg/m(2) every 3 weeks was superior to solvent-based paclitaxel 175 mg/m(2) every 3 weeks for the primary endpoint of overall response rate (33 % vs 19 %; P = 0.001). Subsequently, a number of trials have examined different schedules, doses, and combinations in efforts to optimize nab-paclitaxel-based therapy for metastatic and early-stage breast cancer. The goal of this review is to evaluate the clinical experiences to date with nab-paclitaxel as a single agent or in combination with targeted agents in different treatment settings - with a focus on the feasibility of administration, adverse event profile, and standard efficacy endpoints, such as overall survival, progression-free survival, overall response rate, and pathologic complete response rate. In general, weekly dosing during the first 3 of 4 weeks appears to achieve the best clinical benefit in both the metastatic and early-stage settings. Furthermore, the data suggest that high doses of nab-paclitaxel, such as 150 mg/m(2) during first 3 of 4 weeks or 260 mg/m(2) every 2 weeks, may be more feasible and appropriate for treatment of early-stage disease compared with metastatic disease. Intense regimens of nab-paclitaxel may not be the best treatment approach for unselected patients with metastatic breast cancer, but may suit a subset of patients for whom immediate disease control is required. The growing number of nab-paclitaxel trials in breast cancer will lead to greater refinements in tailoring therapy to patients based on their individual disease and patient characteristics.