Source: DGNews  |  Posted 3 years ago

By Jill Stein

SAN ANTONIO, Tex -- December 15, 2008 -- Ixabepilone on top of capecitabine improves progression-free survival in women with metastatic breast cancer resistant to taxanes and resistant to or pretreated with an anthracycline, researchers reported at the 31st Annual San Antonio Breast Cancer Symposium (SABCS).

Henri Roche, MD, PhD, Institut Claudius Regaud, Toulouse, France, and colleagues reported results from a prespecified pooled subset of resistant patients from 2 phase 3 trials in a poster presentation here on December 12.

The efficacy and safety of ixabepilone in combination with capecitabine was assessed in the CA163-046 and 048 studies. In the 2 trials, 1,973 patients with metastatic breast cancer previously treated with an anthracycline and taxane were randomised to receive either ixabepilone (40 mg/m² IV over 3 hours, every 3 weeks) plus capecitabine (1,000 mg/m² orally, twice a day for 14 days, every 3 weeks) or capecitabine alone (1,250 mg/m² orally twice a day for 14 days, every 3 weeks).

The pooled analysis subgroup included 1,137 patients who met strict resistance criteria in the 046 study and were either resistant to (52%) or pretreated with an anthracycline.

For both studies, resistance was defined as disease progression up to 4 months following taxane therapy in the metastatic setting and up to 12 months following adjuvant taxane therapy. Because of similar trial designs and patient populations, individual subset data were pooled to achieve greater statistical power and data precision.

Results showed that the median progression-free survival was prolonged by 1.4 months with ixabepilone plus capecitabine compared to capecitabine monotherapy (5.1 months vs 3.7 months).

A substantial increase in overall response rate was seen with the combination compared with capecitabine alone (39% vs 22%).

Improvement in overall survival with the combination treatment versus capecitabine alone did not reach statistical significance.

The safety of ixabepilone plus capecitabine combination in taxane-resistant metastatic breast cancer patients was manageable and similar to that demonstrated in the overall population.

Dr. Roche noted that this pooled analysis provides the largest published clinical data set recorded to date for patients with metastatic breast cancer resistant to a taxane and resistant to or pretreated with an anthracycline. He concluded that the results provide further support for the effectiveness of ixabepilone plus capecitabine in these patients.

Funding for this trial was provided by Bristol-Myers Squibb Company.

[Presentation title: Ixabepilone Plus Capecitabine Improves Progression Free Survival in Patients With Metastatic Breast Cancer Resistant to Taxanes: A Pooled Analysis From Two Phase III Trials. Abstract 2015]