Five-Year Dosing, Efficacy Results for Nab-Paclitaxel in TNBC

Hope S. Rugo, MD, a medical oncologist and director of the Breast Oncology Clinical Trials Program at University of California, San Francisco, Helen Diller Family Comprehensive Cancer Center, discusses 5-year follow-up data from the CALGB 40502/NCCTG N063H study, which was a randomized phase III trial of weekly paclitaxel compared with nab-paclitaxel (Abraxane) or ixabepilone (Ixempra) with bevacizumab (Avastin) as first-line chemotherapy for locally recurrent or metastatic breast cancer.

At the 4-year median follow-up, the overall results demonstrated inferiority of the ixabepilone arm for both progression-free survival (PFS) and overall survival (OS). Similar results were seen with nab-paclitaxel.

However, a subset analysis showed a trend toward superiority of nab-paclitaxel versus paclitaxel in the triple-negative breast cancer (TNBC) group. In the hormone receptor-positive (HR+) group, investigators found nab-paclitaxel and ixabepilone to be inferior to paclitaxel.

For OS, ixabepilone was inferior, while nab-paclitaxel trended toward inferior in the HR+ subset, although ixabepilone was quite superior for PFS, at 21 months versus 15 months, in the TNBC group.