Craig A. Bunnell

Clinical Activity of Trastuzumab and Vinorelbine in Women With HER2-Overexpressing Metastatic Breast Cancer

PURPOSE To determine the response rate and toxicity profile of trastuzumab administered concurrently with weekly vinorelbine in women with HER2-overexpressing advanced breast cancer. PATIENTS AND METHODS Forty women with HER2-positive (+3 by immunohistochemistry, n = 30; +2 or positive, n = 10) breast cancer were enrolled onto a study of trastuzumab (4 mg/kg x 1, 2 mg/kg weekly thereafter) and vinorelbine (25 mg/m2 weekly, with dose adjusted each week for neutrophil count). Eighty-two percent of women had received prior chemotherapy as part of adjuvant (30%), metastatic (25%), or both (28%) treatment, including substantial portions of patients who had previously received either anthracyclines (20%), taxanes (15%), or both types (38%) of chemotherapy. RESULTS Responses were observed in 30 of 40 patients (overall response rate, 75%, conditional corrected 95% confidence interval, 57% to 89%). The response rate was 84% in patients treated with trastuzumab and vinorelbine as first-line therapy for metastatic disease, and 80% among HER2 +3 positive patients. High response rates were also seen in women treated with second- or third-line therapy, and among patients previously treated with anthracyclines and/or taxanes. Combination therapy was feasible; patients received concurrent trastuzumab and vinorelbine in 93% of treatment weeks. Neutropenia was the only grade 4 toxicity. No patients had symptomatic heart failure. Grade 2 cardiac toxicity was observed in three patients. Prior cumulative doxorubicin dose in excess of 240 mg/m2 and borderline pre-existing cardiac function were associated with grade 2 cardiac toxicity. CONCLUSION Trastuzumab in combination with vinorelbine is highly active in women with HER2-overexpressing advanced breast cancer and is well tolerated.

Trastuzumab and Vinorelbine as First-Line Therapy for HER2-Overexpressing Metastatic Breast Cancer: Multicenter Phase II Trial With Clinical Outcomes, Analysis of Serum Tumor Markers as Predictive Factors, and Cardiac Surveillance Algorithm

PURPOSE Trastuzumab-based therapy improves survival for women with human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer. We conducted a multicenter phase II study to evaluate the efficacy and safety of trastuzumab combined with vinorelbine, and to assess cardiac surveillance algorithms and tumor markers as prognostic tools. PATIENTS AND METHODS Patients with HER2-positive (immunohistochemistry [IHC] 3+-positive or fluorescence in situ hybridization [FISH]-positive) metastatic breast cancer received first-line chemotherapy with trastuzumab and vinorelbine to determine response rate. Eligibility criteria were measurable disease and baseline ejection fraction >or= 50%. Serial testing for HER2 extracellular domain (ECD) was performed. RESULTS Fifty-four women from 17 participating centers were entered onto the study. The overall response rate was 68% (95% confidence interval, 54% to 80%). Response rates were not affected by method of HER2 status determination (FISH v IHC) or by prior adjuvant chemotherapy. Median time to treatment failure was 5.6 months; 38% of patients were progression free after 1 year. Concurrent therapy was quite feasible with maintained dose-intensity. Patients received both chemotherapy and trastuzumab on 90% of scheduled treatment dates. Two patients experienced cardiotoxicity in excess of grade 1; one patient experienced symptomatic heart failure. A surveillance algorithm of screening left ventricular ejection fraction (LVEF) at 16 weeks successfully identified women at risk for experiencing cardiotoxicity. Other acute and chronic side effects were tolerable. Lack of decline in HER2 ECD during cycle 1 predicted tumor progression. CONCLUSION Trastuzumab and vinorelbine constitute effective and well-tolerated first-line treatment for HER2-positive metastatic breast cancer. Patients with normal LVEF can be observed with surveillance of LVEF at 16 weeks to identify those at risk for cardiotoxicity.

Preoperative therapy with trastuzumab and paclitaxel followed by sequential adjuvant doxorubicin/cyclophosphamide for HER2 overexpressing stage II or III breast cancer: a pilot study.

PURPOSE Trastuzumab combined with chemotherapy improves outcomes for women with human epidermal growth factor receptor 2 (HER2) overexpressing advanced breast cancer. We conducted a pilot study of preoperative trastuzumab and paclitaxel, followed by surgery and adjuvant doxorubicin and cyclophosphamide chemotherapy in earlier stage breast cancer. PATIENTS AND METHODS Patients with HER2-positive (2+ or 3+ by immunohistochemistry) stage II or III breast cancer received preoperative trastuzumab (4 mg/kg x 1, then 2 mg/kg/wk x 11) in combination with paclitaxel (175 mg/m(2) every 3 weeks x 4). Patients received adjuvant doxorubicin and cyclophosphamide chemotherapy following definitive breast surgery. Clinical and pathologic response rates were determined after preoperative therapy. Left ventricular ejection fraction and circulating levels of HER2 extracellular domain were measured serially. RESULTS Preoperative trastuzumab and paclitaxel achieved clinical response in 75% and complete pathologic response in 18% of the 40 women on study. HER2 3+ tumors were more likely to respond than 2+ tumors (84% v 38%). No unexpected treatment-related noncardiac toxicity was encountered. Four patients developed grade 2 cardiotoxicity (asymptomatic declines in left ventricular ejection fraction). Baseline HER2 extracellular domain was elevated in 24% of patients and declined with preoperative therapy. Immunohistochemical analyses of posttherapy tumor specimens indicated varying patterns of HER2 expression following trastuzumab-based treatment. CONCLUSION Preoperative trastuzumab and paclitaxel is active against HER2 overexpressing early-stage breast cancer and may be feasible as part of a sequential treatment program including anthracyclines. The observed changes in cardiac function merit further investigation. Correlative analyses of HER2 status may facilitate understanding of tumor response and resistance to targeted therapy.

Phase II Clinical Trial of Ixabepilone (BMS-247550), an Epothilone B Analog, in Patients With Taxane-Resistant Metastatic Breast Cancer

PURPOSE Ixabepilone (BMS-247550) is an epothilone analog that optimizes the properties of naturally occurring epothilone B. Natural epothilones and their analogs promote tumor cell death by binding to tubulin and stabilizing microtubules, causing apoptosis. This international phase II trial assessed the activity of ixabepilone in patients with metastatic breast cancer (MBC) that was resistant to taxane therapy. PATIENTS AND METHODS MBC patients, who had experienced disease progression while receiving or within 4 months of taxane therapy (6 months if adjuvant taxane only), and who had a taxane as their last regimen, received ixabepilone (1- or 3-hour infusion of 50 mg/m(2) or 3-hour infusion of 40 mg/m(2) every 3 weeks). RESULTS Of 49 patients treated with 40 mg/m(2) ixabepilone during 3 hours, 35 (73%) had experienced disease progression within 1 month of their last taxane dose. The response rate was 12% (95% CI, 4.7% to 26.5%). All responses (n = 6) were partial; five of six patients had not responded to prior taxane therapy. In responders, the median response duration was 10.4 months. In 20 patients (41%), stable disease was the best outcome. Median time to progression was 2.2 months (95% CI, 1.4 to 3.2 months); median survival was 7.9 months. For treated patients across all cohorts (intent-to-treat population), the response rate was also 12% (eight of 66). Treatment-related adverse events in the study were manageable and primarily grade 1/2. Treatment-related neuropathy was mostly sensory and mild to moderate. CONCLUSION Ixabepilone (40 mg/m(2) as a 3-hour infusion every 3 weeks) demonstrates promising antitumor activity and an acceptable safety profile in patients with taxane-resistant MBC.

Docetaxel Administered on a Weekly Basis for Metastatic Breast Cancer

PURPOSE To evaluate the safety and efficacy of weekly docetaxel in women with metastatic breast cancer. PATIENTS AND METHODS Twenty-nine women were enrolled onto a study of weekly docetaxel given at 40 mg/m(2)/wk. Each cycle consisted of 6 weeks of therapy followed by a 2-week treatment break, repeated until disease progression or removal from study for toxicity or patient preference. Fifty-two percent of patients had been previously treated with adjuvant chemotherapy; 21% had received prior chemotherapy for metastatic breast cancer, and 31% had previously received anthracyclines. All patients were assessable for toxicity; two patients were not assessable for response but are included in an intent-to-treat analysis. RESULTS Patients received a median of 18 infusions, with a median cumulative docetaxel dose of 720 mg/m(2). There were no complete responses. Twelve patients had partial responses (overall response rate, 41%; 95% confidence interval, 24% to 61%), all occurring within the first two cycles. Similar response rates were observed among subgroups of patients previously treated either with any prior chemotherapy or with anthracyclines. An additional 17% of patients had stable disease for at least 6 months. The regimen was generally well tolerated. There was no grade 4 toxicity. Only 28% of patients had any grade 3 toxicity, most commonly neutropenia and fatigue. Acute toxicity, including myelosuppression, was mild. Fatigue, fluid retention, and eye tearing/conjunctivitis became more common with repetitive dosing, although these side effects rarely exceeded grade 2. Dose reductions were made for eight of 29 patients, most often because of fatigue (n = 5). CONCLUSION Weekly docetaxel is active in treating patients with metastatic breast cancer, with a side effect profile that differs from every-3-weeks therapy.

Phase II Clinical Trial of Ixabepilone (BMS-247550), an Epothilone B Analog, As First-Line Therapy in Patients With Metastatic Breast Cancer Previously Treated With Anthracycline Chemotherapy

PURPOSE There is a need for new agents to treat metastatic breast cancer (MBC) in patients for whom anthracycline therapy has failed or is contraindicated. This study was conducted to assess the efficacy and safety of the novel antineoplastic, the epothilone B analog ixabepilone, in patients with MBC previously treated with an adjuvant anthracycline. PATIENTS AND METHODS Patients were age >or= 18 years and had received a prior anthracycline-based regimen as adjuvant treatment. Ixabepilone as first-line metastatic chemotherapy was administered as a 40 mg/m(2) intravenous infusion during 3 hours every 3 weeks. The primary efficacy end point was objective response rate (ORR). Secondary efficacy end points included duration of response, time to response, time to progression, and survival. RESULTS All 65 patients were assessable for response. Their median age was 52 years (range, 33 to 80 years). ORR was 41.5% (95% CI, 29.4% to 54.4%), median duration of response was 8.2 months (95% CI, 5.7 to 10.2 months), and median time to response was 6 weeks (range, 5 to 17 weeks). Median survival was 22.0 months (95% CI, 15.6 to 27.0 months). Treatment-related adverse events were manageable and mostly grades 1/2: the most common of these (other than alopecia) was mild to moderate neuropathy, which was primarily sensory and mostly reversible in nature. CONCLUSION Ixabepilone is efficacious and has a predictable and manageable safety profile in women with MBC previously treated with an adjuvant anthracycline.

Paroxetine Is an Effective Treatment for Hot Flashes: Results From a Prospective Randomized Clinical Trial

PURPOSE In an open-label trial we have previously demonstrated that paroxetine reduces hot flashes. We initiated a stratified, randomized, double-blind, cross-over, placebo-controlled trial to investigate the efficacy of paroxetine 10 mg and 20 mg compared to placebo in reducing hot flash frequency and composite score. A secondary objective was to evaluate quality of life (QOL) parameters. PATIENTS AND METHODS Women who suffered at least two hot flashes a day for 1 month or longer were eligible. Women were randomly assigned to 4 weeks of paroxetine 10 mg or 20 mg followed by placebo for 4 weeks, or placebo for 4 weeks followed by paroxetine 10 mg or 20 mg for 4 weeks. Participants completed baseline daily hot flash diaries for one week prior to the start of the study and throughout the study, and QOL questionnaires at baseline, week 5 and week 9. RESULTS 279 women were screened, and 151 were randomly assigned. Paroxetine 10 mg reduced hot flash frequency and composite score by 40.6% and 45.6%, respectively, compared to 13.7% and 13.7% for placebo (P = .0006 and P = .0008, respectively). Paroxetine 20 mg reduced hot flash frequency and composite score by 51.7% and 56.1%, respectively, compared with 26.6% and 28.8% for placebo (P = .002 and P = .004, respectively). Efficacy was similar between the two doses, but women were less likely to discontinue low-dose paroxetine. Paroxetine 10 mg was associated with a significant improvement in sleep compared with placebo (P = .01). CONCLUSION Paroxetine is an effective treatment for hot flashes in women with or without a prior breast cancer.

Phase I/II Study of Ixabepilone plus Capecitabine in Anthracycline–Pretreated/Resistant and Taxane-Resistant Metastatic Breast Cancer

PURPOSE The aim of this study was to determine the safety, maximum tolerated dose (MTD), recommended phase II dose, and efficacy of the epothilone B analogue ixabepilone plus capecitabine in anthracycline-pretreated/ resistant and taxane-resistant metastatic breast cancer (MBC). PATIENTS AND METHODS A total of 106 patients were enrolled. The study consisted of a dose-escalation phase (phase I) and a tumor response rate evaluation phase (phase II). Seventy-four patients were treated in phase I with schedule A (ixabepilone 40 mg/m2 intravenously on day 1 plus capecitabine 1650-2000 mg/m2 on days 1-14 of a 21-day cycle) or schedule B (ixabepilone 8-10 mg/m2 on days 1-3 plus capecitabine 1650 mg/m2 on days 1-14 of a 21- day cycle). RESULTS No dose-limiting toxicities (DLTs) were observed in the 8/1650 mg/m2 and 10/1650 mg/m2 cohorts; 1 of 30 patients in the 40/1650 mg/m2 cohort and 2 of 30 patients in the 40/2000 mg/m2 cohort had a DLT consisting of grade 3 plantar-palmar erythrodysesthesia (PPE). The 40/2000 mg/m2 dose was defined as the MTD for schedule A, and a total of 62 patients were treated for the phase II portion of the trial, which examined tumor response. The objective response rate was 30%, median time-to-response was 6 weeks, median duration of response was 6.9 months, and median progression-free survival was 3.8 months. Grade 3/4 treatment-related events in phase II included fatigue (34%), PPE (34%), myalgia (23%), nausea (16%), peripheral neuropathy (19%), and diarrhea/vomiting (10%). Grades 3/4 neutropenia (69%) and leukopenia (55%) were managed primarily by dose reduction/treatment interruption. CONCLUSION Ixabepilone plus capecitabine demonstrated clinical activity and an acceptable safety profile in patients with anthracycline-pretreated/resistant and taxane-resistant MBC. Ixabepilone was recently approved in the United States for the treatment of resistant/refractory locally advanced or MBC.

Efficacy of Pegfilgrastim and Darbepoetin Alfa As Hematopoietic Support for Dose-Dense Every-2-Week Adjuvant Breast Cancer Chemotherapy

PURPOSE Dose-dense, every-2-week adjuvant chemotherapy using doxorubicin/cyclophosphamide (AC; 60/600 mg/m2 every 2 weeks x four cycles) followed by paclitaxel (175 mg/m2 every 2 weeks x four cycles), requiring filgrastim on days 3 through 10 of each cycle has been shown to improve survival compared with every-3-week treatment schedules but is associated with greater risk of RBC transfusion (13%). The role of long-acting hematopoietic growth factors in facilitating every-2-week chemotherapy and minimizing hematologic toxicity has not been established. PATIENTS AND METHODS Women with stage I to III breast cancer received dose-dense AC --> paclitaxel as neoadjuvant or adjuvant chemotherapy. Patients received pegfilgrastim 6 mg subcutaneous (SQ) on day 2 of each cycle. Darbepoetin alfa was initiated at 200 microg SQ every 2 weeks for hemoglobin < or = 12 g/dL, and administered thereafter, according to a preplanned algorithm. The primary end points were to evaluate the percentage of patients with febrile neutropenia and the percentage of patients requiring RBC transfusion. RESULTS Among 135 women treated on this single arm study, there were two cases of febrile neutropenia (incidence 1.5%). No patients received RBC transfusion. Darbepoetin alfa therapy was initiated in 92% of patients. The modest leukocytosis seen during paclitaxel cycles was attributable, in part, to corticosteroid premedication. Other toxicity and dose-delivery were similar to dose-dense AC --> paclitaxel in Cancer and Leukemia Group B 9741. CONCLUSION Pegfilgrastim and darbepoetin alfa are effective and safe in facilitating every-2-week AC --> paclitaxel, minimizing rates of febrile neutropenia and RBC transfusion.

The presence of membrane-bound stem cell factor on highly immature nonmetachromatic mast cells in the peripheral blood of a patient with aggressive systemic mastocytosis

BACKGROUND Systemic mastocytosis is characterized by mast cell infiltration of bone marrow and tissues in the absence of identified circulating bone marrow-derived progenitors. A 58-year-old man was first seen with aggressive systemic mastocytosis manifested by urticaria pigmentosa, hepatosplenomegaly, generalized bone lesions, anemia, thrombocytopenia, monoclonal gammopathy, and increased urine histamine levels. OBJECTIVES AND METHODS A rapidly progressive anemia and thrombocytopenia dictated a splenectomy. We sought to identify the mast cell progenitors in the peripheral blood and to provide evidence of their maturation in tissues with immunohistochemical and ultrastructural analyses. RESULTS The peripheral blood contained 1% to 3% nonmetachromatic mononuclear cells with eccentric nuclei that expressed the mast cell proteases, tryptase and carboxypeptidase A, along with c-kit, stem cell factor (SCF), and high-affinity IgE receptor (Fc epsilon RI), but not chymase. Similar mononuclear cells colocalized in the spleen and lymph nodes with mature, metachromatic mast cells that expressed tryptase, chymase, carboxypeptidase A, c-kit, SCF, and Fc epsilon RI. Electron microscopy disclosed, at each site, a mature mast cell population with electron-dense, scroll-poor granules. CONCLUSIONS The peripheral blood of a patient with aggressive systemic mastocytosis contained immature mononuclear cells of the mast cell lineage that express c-kit, SCF, tryptase, carboxypeptidase A, and Fc epsilon RI. These cells were also found in the skin, spleen, and lymph nodes where they presumably expand, differentiate, and mature, assuming the mast cell phenotype for those tissues characterized by metachromasia, expression of a full range of mast cell-related secretory granule proteases, and ultrastructural appearance. The presence of SCF on the surface membrane of the circulating, highly immature mast cells suggests an autocrine regulation of the c-kit-SCF interaction.