Purpose: Effective treatment options for patients with metastatic breast cancer pretreated with or resistant to anthracyclines and taxanes are limited. Ixabepilone has single-agent activity in these patients and has demonstrated synergy with capecitabine in this setting. This study was designed as a prospective clinical trial to evaluate the efficacy and safety of ixabepilone plus capecitabine in both anthracycline-pretreated and resistant and taxane-resistant metastatic breast cancer of Chinese women.
Patients and methods: Patients with measurable disease who had anthracycline and taxanes as prior neoadjuvant, adjuvant or metastatic therapy were treated with ixabepilone at 40 mg/m(2) intravenously on day 1 of 21-day cycle plus capecitabine 2,000 mg/m(2) orally on day 1 through 14 of a 21-day cycle. The primary end point was the objective response rate. The secondary end points were time to progression, overall survival, and toxicity profiles.
Results: Twenty-one patients received 146 cycles with a median of 5 cycles (range 1-13 cycles) per patients. Fourteen patients (66.7%) had partial response, 5 patients (23.8%) had stable disease, and 2 patients (9.5%) had progressive disease. Median time to progression and duration of response were 6.2 and 6.0 months, respectively. The median overall survival was 16.7 months. Eight (38.1%) patients required dose reduction and 14 (66.7%) patients discontinued treatment for adverse effect. Grade 3/4 treatment-related events included fatigue (28.6%), peripheral sensory neuropathy (33.3%), neutropenia (61.9%), anemia (4.7%), hypokalemia (4.7%), hand and foot syndrome (19.0%) and infection (9.5%). Resolution of grade 3/4 peripheral neuropathy was reversible after a median period of 6 weeks.
Conclusion: Ixabepilone plus capecitabine demonstrated a clear activity and an acceptable safety profile in Chinese patients with anthracycline-pretreated/resistant and taxane-resistant metastatic breast cancer, and the majority of patients completed 6 cycles of the therapy with manageable neuropathy toxicities.