Phase III results show Abraxane leads to high disease-free survival rates in breast cancer

The German Breast Group and Celgene announced long-term invasive disease-free survival results from the GeparSepto clinical trial comparing the investigational use of Abraxane (paclitaxel albumin-bound particles for injectable suspension) to paclitaxel in early high-risk breast cancer patients. The results from the 1,206 patient study found that Abraxane demonstrated a significantly higher disease-free survival rate, a secondary efficacy endpoint, in high risk early breast cancer patients when compared to conventional solvent-based paclitaxel.

In this large Phase III study, of which disease-free survival was a secondary endpoint, the investigational use of Abraxane (N=600) was compared to conventional solvent-based paclitaxel (N=606) followed by epirubicin/cyclophosphamide in both arms given all before surgery. The study found a significantly higher disease-free survival (DFS) rate in patients receiving Abraxane compared to those receiving paclitaxel as part of a neoadjuvant treatment regimen [HR=0.69, 95% CI (0.54-0.89); p=0.0044]). The rates of DFS were 87.1% vs. 80.7% at 3 years and 83.5% vs. 76.2% at 4 years, respectively. A treatment effect was observed in the predefined subset of patients with triple negative tumors and hormone receptor-positive (HR+), human epidermal growth factor receptor 2 negative (HER2-) tumors. Patients with triple negative breast cancer (n=276) had DFS rates of 83.1% vs. 73.4% at 3 years, and 78.7% vs. 68.6% at 4 years. DFS was not significantly different in the TNBC subgroup [HR=0.66, 95% CI (0.42-1.04), p=0.0694]. HR+/HER2- patients had DFS rates of 86.3% vs. 78.6% at 3 years and 80.8% vs. 72.8% at 4 years [HR=0.71, 95% CI (0.49-1.02); p=0.0660].

Another secondary endpoint measure evaluated in the study was overall survival (OS). No difference in OS was observed, however the OS findings are not yet mature. Data were presented at the 2017 San Antonio Breast Cancer Symposium (SABCS).