TITAN: phase III study of doxorubicin/cyclophosphamide followed by ixabepilone or paclitaxel in early-stage triple-negative breast cancer.

PURPOSE: Ixabepilone is a microtubule stabilizer with activity in taxane-refractory metastatic breast cancer and low susceptibility to taxane-resistance mechanisms including multidrug-resistant phenotypes and high ß-III tubulin expression. Since these resistance mechanisms are common in triple-negative breast cancer (TNBC), ixabepilone may have particular advantages in this patient population. This study evaluated the substitution of ixabepilone for paclitaxel following doxorubicin/cyclophosphamide (AC) in the adjuvant treatment of early-stage TNBC. METHODS: Patients with operable TNBC were eligible following definitive breast surgery. Patients were randomized (1:1) to receive four cycles of AC followed by either four cycles (12 weeks) of ixabepilone or 12 weekly doses of paclitaxel. RESULTS: 614 patients were randomized: 306 to AC/ixabepilone and 308 to AC/paclitaxel. At a median follow-up of 48 months, 59 patients had relapsed (AC/ixabepilone, 29; AC/paclitaxel, 30). The median time from diagnosis to relapse was 20.8 months. The 5-year disease-free survival (DFS) rates of the two groups were similar [HR 0.92; ixabepilone 87.1% (95% CI 82.6-90.5) vs. paclitaxel 84.7% (95% CI 79.7-88.6)]. The estimated 5-year overall survival (OS) rates were also similar [HR 1.1; ixabepilone 89.7% (95% CI 85.5-92.7) vs. paclitaxel 89.6% (95% CI 85.0-92.9)]. Peripheral neuropathy was the most common grade 3/4 event. Dose reductions and treatment discontinuations occurred more frequently during paclitaxel treatment. CONCLUSIONS: Treatment with AC/ixabepilone provided similar DFS and OS in patients with operable TNBC when compared to treatment with AC/paclitaxel. The two regimens had similar toxicity, although treatment discontinuation, dose modifications, and overall peripheral neuropathy were more frequent with AC/paclitaxel. TRIAL REGISTRATION: Clinical Trials.gov Identifier, NCT00789581.

Phase II multicenter study of docetaxel and bevacizumab with or without trastuzumab as first-line treatment for patients with metastatic breast cancer.

BACKGROUND: Adding bevacizumab to docetaxel or paclitaxel in the first-line improves the progression-free survival (PFS) of metastatic breast cancer (MBC) patients. Docetaxel has been studied with bevacizumab at the maximally tolerated dose of 100 mg/m(2). We investigated the effects of combining bevacizumab with docetaxel (75 mg/m(2)) with or without trastuzumab for human epidermal growth factor receptor 2-positive (HER2(+)) and HER2-negative (HER2(-)) patients, respectively. PATIENTS AND METHODS: We conducted a phase II study, stratified by HER2 status, of patients with locally advanced breast cancer or MBC who had received no prior chemotherapy for metastatic disease and showed no evidence or history of central nervous system metastases. Stratum 1 (HER2(-)) treatment consisted of bevacizumab (15 mg/kg) followed by docetaxel (75 mg/m(2)) administered every 3 weeks; stratum 2 (HER2(+)) treatment was the same as that of stratum 1 with the addition of trastuzumab (8 mg/kg loading dose on day 2 of cycle 1, and 6 mg/kg on day 1 of all subsequent cycles). RESULTS: The trial accrued 73 patients (stratum 1, 52 patients; stratum 2, 21 patients). The most common grade 3 or 4 adverse event (all strata) was fatigue (stratum 1, 11.5%; stratum 2, 10%). The incidence of grade 3 hypertension was 6% for stratum 1 and 5% for stratum 2. The median PFS was 8.4 months (95% CI, 5.2-10.4 months) in stratum 1; the median PFS in stratum 2 was 13.3 months (95% CI, 11.9-35.4 months). The overall response rate for stratum 1was 58% and for stratum 2 was 81%, and the clinical benefit rates were 67% and 81%, respectively. CONCLUSION: In first-line treatment of MBC, adding docetaxel (75 mg/m(2)) to bevacizumab administered every 3 weeks in HER2(-) patients, and docetaxel plus trastuzumab plus bevacizumab treatment in HER2(+) patients are feasible and safe, with high response rates and promising PFS compared with those of bevacizumab-naive historic controls.