ABSTRACT
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.
Subject(s)
Cyclophosphamide/administration & dosage , Doxorubicin/administration & dosage , Epothilones/administration & dosage , Paclitaxel/administration & dosage , Triple Negative Breast Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cyclophosphamide/adverse effects , Disease-Free Survival , Doxorubicin/adverse effects , Drug Administration Schedule , Epothilones/adverse effects , Female , Humans , Middle Aged , Neoplasm Staging , Paclitaxel/adverse effects , Survival Analysis , Treatment Outcome , Triple Negative Breast Neoplasms/pathology , Young AdultABSTRACT
BACKGROUND: Targeting epidermal growth factor receptors (EGFRs) has been a novel strategy in treating non-small-cell lung cancer (NSCLC). This multicenter, community-based trial was designed to examine the role of cetuximab in combination with a nonplatinum regimen. PATIENTS AND METHODS: Eligibility criteria were newly diagnosed unresectable stage III/IV NSCLC, all histologies, measurable disease, and Eastern Cooperative Oncology Group performance status (ECOG PS) 0-2. Treatment premedication included dexamethasone 20 mg orally 12 and 6 hours before treatment, and 4 mg 12 hours following treatment; diphenhydramine 50 mg intravenously (I.V.) and cimetidine 300 mg I.V. before cetuximab. Treatment medication included docetaxel 30 mg/m2 I.V. days 1 and 8; gemcitabine 1000 mg/m2 I.V. days 1 and 8; and cetuximab 400 mg/m2 I.V. day 1, then 250 mg/m2 I.V. weekly. Patients received up to 6 cycles with restaging every 6 weeks. The primary endpoint was an overall response rate (ORR) > or = 25%. RESULTS: Sixty-nine patients enrolled from July 2005 to October 2007. Patients had a median age of 69 years; 70% were male and 30% were female; ECOG PS was 0 in 42%, 1 in 51%, and 2 in 7%; patients had adenocarcinoma (42%), squamous cell (30%), large cell (6%), mixed (1%), and not otherwise specified (20%) disease. The ORR was 17% (95% CI, 9%-29%). Thirty-five patients (54%) had stable disease; 14 patients (22%) had progressive disease. With a median follow-up of 17.8 months, the median progression-free and overall survivals were 4 months and 9.4 months, respectively. The most common (> 10%) grade 3/4 toxicities were neutropenia (25%), rash (22%), and fatigue (12%). Accrual in our middle Tennessee offices was temporarily suspended and ultimately stopped because of a higher-than-anticipated rate of cetuximab-related severe hypersensitivity reactions (HSRs) in 4 patients among the first 12 enrolled, including 1 fatal event. CONCLUSION: Cetuximab/docetaxel/gemcitabine was relatively well-tolerated and associated with efficacy similar to chemotherapy alone. Additional study with cetuximab/chemotherapy in NSCLC should focus on new potentially predictive biomarkers. Also, additional study is needed to better understand and prevent the severe HSRs that appear to be endemic to specific regions of the United States.