Source: DGNews  |  Posted 3 years ago

By Bruce Sylvester

SAN ANTONIO, Tex -- December 15, 2008 -- Ixabepilone plus capecitabine is the first combination regimen to show a statistically significant benefit in progression-free survival (PFS) for women with advanced, triple-negative-tumour, metastatic breast cancer, according to an analysis of data from 2 phase 3 trials.

The findings were presented on December 13 here at the 31st Annual San Antonio Breast Cancer Symposium (SABCS).

"This pooled analysis provides the largest clinical data set recorded for patients with triple-negative metastatic breast cancer," said lead investigator Hope Rugo, MD, University of California, San Francisco, San Francisco, California.

Dr. Rugo noted that in these patients, ixabepilone plus capecitabine prolonged the median PFS by 2.5 months and doubled the overall response rate, but it did not significantly increase the overall survival rate compared to capecitabine monotherapy.

The 1,973 women with metastatic breast cancer were previously treated with an anthracycline and a taxane in 2 phase 3 randomised trials to receive either ixabepilone 40 mg/m² IV over 3 hours Q3W plus capecitabine 1,000 mg/m² PO BID for 14 days Q3W or capecitabine monotherapy 1,250 mg/m² PO BID for 14 days Q3W.

A subgroup of 443 women were diagnosed with advanced, triple-negative-tumour, metastatic breast cancer. "Due to the similarity of the study populations, individual patient data from both studies was pooled to better evaluate treatment effect within preplanned patient subgroups," the authors noted.

For PFS and overall response (OR), 191 of the ixabepilone plus capecitabine subjects and 208 of the capecitabine monotherapy subjects had evaluable data. The investigators reported a median PFS rate of 4.2 months for combination therapy and 1.7 months for monotherapy. They reported an OR rate of 31% for combination therapy and 15% for monotherapy.

For overall survival, they reported a median of 10.3 months for combination therapy and 9.0 months for monotherapy.

"Promising activity exhibited by ixabepilone plus capecitabine warrants future studies to establish ixabepilone as the preferred treatment option for patients with triple-negative breast cancer," the investigators concluded.

Funding for this study was provided by Bristol-Myers Squibb.

[Presentation title: Ixabepilone Plus Capecitabine vs Capecitabine in Patients With Triple Negative Tumours: A Pooled Analysis of Patients From Two Large Phase III Clinical Studies. Abstract 3057]