Interaction between Herceptin and taxanes

The taxanes and Herceptin have been shown to possess significant clinical activity in metastatic breast cancer. Preclinical testing of taxane/Herceptin combinations demonstrated additive and synergistic interactions with paclitaxel and docetaxel, respectively. In a pivotal clinical trial, combination of paclitaxel (3-weekly) and Herceptin was associated with an increased response rate compared with paclitaxel monotherapy (41% vs. 17%; p = 0.001). The combination therapy also significantly improved time to disease progression (6.9 vs. 2.7 months; p < 0.05). In a phase II study of weekly paclitaxel plus Herceptin in patients with normal or increased tumor HER2 levels, a response was observed in 60% of patients and the regimen was well tolerated. Responses were more frequent in patients with HER2-overexpressing tumors (83% vs. 45%). Preliminary results from a phase II study of Herceptin plus docetaxel in patients with HER2-overexpressing tumors indicate significant activity, with a response observed in 7 (44%) of 16 evaluable patients. The preliminary results of a trial of weekly docetaxel and Herceptin demonstrate a response rate of 54% in 13 evaluable patients. Additional European trials of Hercep- tin/taxane combinations as first- and second-line and adjuvant therapy are ongoing. The results of the studies to date indicate that regimens combining Herceptin with 3-weekly and weekly taxane are effective and well tolerated.