670 Phase III comparison of docetaxel (D)and pacilitaxel (P) in patients with metastatic breast cancer (MBC)

Regulation of mitosis and taxane response by Daxx and Rassf1

Current theories suggest that mitotic checkpoint proteins are essential for proper cellular response to taxanes, a widely-used family of chemotherapeutic compounds. We recently demonstrated that absence or depletion of protein Daxx increases cellular taxol (paclitaxel) resistance—a common trait of patients diagnosed with several malignancies, including breast cancer. Further investigation of Daxx-mediated taxol response revealed that Daxx is important for the proper timing of mitosis progression and cyclin B stability. Daxx interacts with mitotic checkpoint protein Rassf1 and partially co-localizes with this protein during mitosis. Rassf1/Daxx depletion or expression of Daxx binding domain of Rassf1 elevates cyclin B stability and increases taxol resistance in cells and mouse xenograft models. In breast cancer patients, we observed the inverse correlation between Daxx and clinical response to taxane-based chemotherapy. These data suggest that Daxx and Rassf1 define a mitotic stress checkpoint that enables cells to exit mitosis as micronucleated cells (and eventually die) when encountered with specific mitotic stress stimuli, including taxol. Surprisingly, depletion of Daxx or Rassf1 does not change activity of E3 ubiquitin ligase APC/C in in vitro settings, suggesting necessity of mitotic cellular environment for proper activation of this checkpoint. Daxx and Rassf1 may become useful predictive markers for the proper selection of patients for taxane chemotherapy.

Gemcitabine and split-dose paclitaxel or docetaxel in metastatic breast cancer: A randomised phase II study

PURPOSE

The purpose was to evaluate the activity and toxicity of split-dose paclitaxel or docetaxel in combination with gemcitabine in patients with metastatic breast cancer (MBC) who had previously received anthracyclines.

PATIENTS AND METHODS

A total of 210 patients were randomly assigned to one of three treatment arms: gemcitabine 1,250 mg/m(2) Days 1 and 8 and paclitaxel 175 mg/m(2) as a 3-h infusion on Day 1 (GP1); gemcitabine 1,000 mg/m(2) Days 1 and 8 and paclitaxel 100 mg/m(2) as a 1-h infusion on Days 1 and 8 (GP2); gemcitabine 1,000 mg/m(2) Days 1 and 8 and docetaxel 40 mg/m(2) as a 1-h infusion on Days 1 and 8 (GD). Cycles were repeated every 3 weeks.

RESULTS

For the 204 patients evaluable for response assessment, the response rates were 48.6% for GP1, 52.2% for GP2, and 52.3% for GD. Median response duration, time to treatment failure, and time to progression (TTP) were similar in each arm. Median TTP for GP1, GP2 and GD was 7.5, 7.0 and 7.4 months, respectively. For the 208 patients evaluable for safety, the most common grade 3/4 toxicity for each regimen was neutropaenia, with 64%, 57%, and 68% for GP1, GP2, and GD, respectively. Grade 4 neutropaenia, grade 3/4 anaemia, febrile neutropaenia, and diarrhoea were more common in the docetaxel arm, as was the use of intravenous antibiotics and blood transfusions.

CONCLUSION

The study confirmed the high activity of gemcitabine-taxane combinations in MBC. Split-dose paclitaxel had similar activity and toxicity to the 3-weekly administration. The split-dose docetaxel regimen had similar activity to the paclitaxel combinations though associated with higher toxicity.

Peripheral neuropathy induced by microtubule-stabilizing agents

Microtubule-stabilizing agents (MTSAs), including the taxanes and epothilones, are effective chemotherapeutic agents for the treatment of many cancers. Neuropathy is a major adverse effect of MTSA-based chemotherapy, with severe peripheral neuropathy (grade 3 or 4) occurring in as many as 30% of patients treated with a MTSA. MTSA-induced neuropathy usually resolves gradually after cessation of the treatment. The most reliable method to accurately assess MTSA-induced neuropathy is by clinical evaluation, although additional techniques are being developed and evaluated. Among MTSA-induced neuropathy, the most extensively studied is that induced by taxanes; such a neuropathy usually presents as sensory neuropathy and is more common with paclitaxel than docetaxel. The incidence of MTSA-induced neuropathy seems to depend on the MTSA dose per treatment cycle, the schedule of treatment, and the duration of the infusion. Although there have been several small clinical trials with neuroprotective agents, early recognition and supportive care are the best approaches for prevention and management of MTSA-induced neuropathy. In the future, research should focus on elucidating the mechanism of MTSA-induced neuropathy, developing reliable in vivo and in vitro preclinical models to study MTSA-induced neuropathy, developing a more reliable grading system for MTSA-induced neuropathy, developing more reliable methods for evaluating MTSA-induced neuropathy, and evaluating the efficacy of potential neuroprotective agents in clinical trials.

A phase I dose finding study of cisplatin, gemcitabine, and weekly docetaxel for patients with advanced transitional cell cancer

OBJECTIVE

Efficacious regimens are needed for the treatment of metastatic bladder cancer. The aim of this study was to determine the toxicity and phase II dose of a triplet regimen of cisplatin, gemcitabine, and weekly docetaxel for patients with advanced transitional cell carcinoma.

METHODS

Thirteen patients were enrolled to the study: 3 to dose level 1 (cisplatin 70 mg/m2 on day 1; gemcitabine 1000 mg/m2, day 1 and 8; and docetaxel 30 mg/m2, day 1 and 8, every 21 days), and 10 to dose level -1 (cisplatin 70 mg/m2 on day 1; gemcitabine 800 mg/m2, day 1 and 8; and docetaxel 30 mg/m2, day 1 and 8, every 21 days).

RESULTS

Grade 3-4 hematologic toxicities included neutropenia (40%) and thrombocytopenia (20%). Grade 3 nonhematologic toxicity was restricted to diarrhea. There were 2 early deaths: 1 from a suspected pulmonary embolism and another from sepsis. In 11 patients who received > or =2 cycles the response rate was 73%.

CONCLUSIONS

The recommended phase II dose of this triplet regimen in advanced transitional cell carcinoma is cisplatin 70 mg/m2 on day 1; gemcitabine 800 mg/m2 day 1 and 8; and docetaxel 30 mg/m2 day 1 and 8, repeated every 21 days. The preliminary objective response rate was high in this cohort of patients.

Docetaxel in the management of ovarian cancer

Standard first-line treatment for Stage IC-IV ovarian cancer is currently a platinum agent or a combination of a platinum agent with a taxane. The use of a taxane compound in addition to single-agent platinum is increasingly preferred to platinum alone. In countries such as the UK, the taxane paclitaxel has been approved by the government for first-line use. However, it has yet to receive US Food and Drug Administration approval in the USA for use in this context. Typically, in countries such as the UK, patients with advanced ovarian cancer receive a combination of paclitaxel and carboplatin first line, both drugs given 3-weekly by intravenous infusion. Subsequent trials have demonstrated that the second-generation taxane docetaxel can be used as a substitute for paclitaxel; sharing many of its actions but with a different toxicity profile. However, docetaxel has not yet received approval for standard use. Here, the clinical development of docetaxel and its present and future place in the management of ovarian cancer is discussed.

High thioredoxin expression is associated with resistance to docetaxel in primary breast cancer

PURPOSE

Thioredoxin overexpression is suggested to be associated with resistance to several chemotherapeutic agents in vitro. In the present study, it has been studied whether or not high thioredoxin expression is associated with resistance to docetaxel therapy in breast cancer patients.

PATIENTS AND METHODS

Sixty-three primary breast cancer patients were treated with docetaxel (60 mg/m(2), q3w) for four cycles in the neoadjuvant setting. Expression of thioredoxin, estrogen receptor (ER), p53, BRCA-1, and Bcl-2 in tumor tissues obtained before docetaxel therapy was studied by immunohistochemistry (thioredoxin, p53, BRCA-1, and Bcl-2) and enzyme immunoassay (ER), and relationship of expression of these biomarkers with a pathologic response was investigated.

RESULTS

There was no significant correlation between the expression of p53, BRCA-1, or Bcl-2 and a response to docetaxel. However, tumors with high thioredoxin expression showed a significantly lower response rate (0%) than those with low thioredoxin expression (30.6%; P = 0.018) and ER-negative tumors showed a significantly higher response rate (32.4%) than ER-positive tumors (10.7%; P = 0.043). Thioredoxin expression significantly increased after docetaxel therapy (mean, 56.1%) as compared with that before docetaxel therapy (mean, 28.6%; P < 0.0001) but there was no significant association between the extent of increase in thioredoxin expression and response.

CONCLUSION

High thioredoxin expression in prechemotherapy tumor samples, but not the increase in thioredoxin expression induced by docetaxel, is associated with resistance to docetaxel in breast cancer. Thioredoxin and ER might be clinically useful in the prediction of a response to docetaxel.

The best use of adjuvant chemotherapy: New drugs and new use of “old” drugs

Modern chemotherapy has diminished the risks of distant relapse and death in many subgroups of patients with early stage breast cancer. Although the initial trials relied on empirically designed regimens, studies are increasingly based on preclinical science and reflect the growing understanding of the molecular basis of cancer. Empiric clinical trials proved the worth of combination chemotherapy, the limited value of very long courses of treatment, and the benefits of adding first anthracyclines and then later taxanes. More recent trials have demonstrated the limits on empiric dose escalation and the benefits of optimized scheduling. Many trials are currently focused on novel targeted agents. Based on several decades of studies in thousands of women it is reasonable to consider a combination of chemotherapy agents for patients with hormone unresponsive or otherwise high-risk tumors. Anthracyclines and taxanes should be incorporated into the treatment plans of patients in the higher risk subsets and the specific regimens should be taken from the several randomized studies. When available, eligible patients should be enrolled on prospective clinical trials.

Docetaxel/Gemcitabine Administered Every Other Week as First-Line Treatment for Metastatic Breast Cancer: Final Results of a Phase II Trial

BACKGROUND

The purpose of this study was to assess the toxicity and efficacy of the combination of docetaxel and gemcitabine every 2 weeks as first-line therapy in metastatic breast cancer.

PATIENTS AND METHODS

We selected patients between the ages of 18 years and 70 years with a Karnofsky performance status of > or = 60 to receive docetaxel 65 mg/m(2) followed by gemcitabine 2500 mg/m(2) on day 1 every 14 days for 10 cycles. Patients could receive more cycles at the discretion of investigator.

RESULTS

Of the 52 patients entered, 48 were evaluable for efficacy and toxicity. The overall response rate was 75% (95% confidence interval, 60%-86%), with 8 patients (17%) exhibiting a complete response. The median time to progression was 10.7 months, and the median survival was 32.2 months. The predominant grade 3/4 hematologic toxicity was neutropenia (44% of patients), and the predominant grade 3/4 nonhematologic toxicity was asthenia (15% of patients). Other grade 3/4 toxicities, such as anemia, nausea/vomiting, and diarrhea, were present but infrequent (< or = 10% of patients). The relative dose intensities of both drugs were > 88%.

CONCLUSION

The combination of docetaxel/gemcitabine once every 2 weeks is active and well tolerated in patients with untreated advanced breast carcinoma. This chemotherapy regimen might be useful in advanced breast cancer when anthracycline combinations are not preferred, such as cases previously treated with adjuvant anthracycline chemotherapy.

Phase III trial of nanoparticle albumin-bound paclitaxel compared with polyethylated castor oil-based paclitaxel in women with breast cancer

PURPOSE

ABI-007, the first biologically interactive albumin-bound paclitaxel in a nanameter particle, free of solvents, was compared with polyethylated castor oil-based standard paclitaxel in patients with metastatic breast cancer (MBC). This phase III study was performed to confirm preclinical studies demonstrating superior efficacy and reduced toxicity of ABI-007 compared with standard paclitaxel.

PATIENTS AND METHODS

Patients were randomly assigned to 3-week cycles of either ABI-007 260 mg/m(2) intravenously without premedication (n = 229) or standard paclitaxel 175 mg/m(2) intravenously with premedication (n = 225).

RESULTS

ABI-007 demonstrated significantly higher response rates compared with standard paclitaxel (33% v 19%, respectively; P = .001) and significantly longer time to tumor progression (23.0 v 16.9 weeks, respectively; hazard ratio = 0.75; P = .006). The incidence of grade 4 neutropenia was significantly lower for ABI-007 compared with standard paclitaxel (9% v 22%, respectively; P < .001) despite a 49% higher paclitaxel dose. Febrile neutropenia was uncommon (< 2%), and the incidence did not differ between the two study arms. Grade 3 sensory neuropathy was more common in the ABI-007 arm than in the standard paclitaxel arm (10% v 2%, respectively; P < .001) but was easily managed and improved rapidly (median, 22 days). No hypersensitivity reactions occurred with ABI-007 despite the absence of premedication and shorter administration time.

CONCLUSION

ABI-007 demonstrated greater efficacy and a favorable safety profile compared with standard paclitaxel in this patient population. The improved therapeutic index and elimination of corticosteroid premedication required for solvent-based taxanes make the novel albumin-bound paclitaxel ABI-007 an important advance in the treatment of MBC.

Weekly Docetaxel and Gemcitabine as First-Line Treatment for Metastatic Breast Cancer: Results of a Multicenter Phase II Study

OBJECTIVES

We conducted a multicenter phase II study to evaluate the clinical efficacy, toxicity, and dose intensity of a new weekly schedule of docetaxel and gemcitabine as first-line treatment of metastatic breast cancer patients.

METHODS

We enrolled 58 patients, 52% of whom had received a previous anthracycline-containing chemotherapy. The treatment schedule was: docetaxel 35 mg/m2 and gemcitabine 800 mg/m2 i.v. on days 1, 8, 15 every 28 days.

RESULTS

All patients were assessable for toxicity and 56 for efficacy. Overall response rate was 64.3% with 16.1% of complete responses and 48.2% of partial responses. Median survival was 22.10 months (95% CI: 15.53-28.67) and median time to tumor progression was 13.6 months (95% CI: 10.71-16.49). The most common hematological toxicity was neutropenia (no febrile neutropenia), which occurred in 28 patients (48.3%) but grade 3-4 in only 8 patients (14%). Alopecia, the most common nonhematological toxicity, occurred in 20 (34.5%) patients, but only 5 patients (8.6%) experienced grade 3 alopecia.

CONCLUSION

The activity of docetaxel and gemcitabine in metastatic breast cancer is confirmed. The promising results of the employed schedule, in agreement with other published studies, need to be further confirmed within a phase III study.

Cisplatin plus oral etoposide (EoP) combination is more effective than paclitaxel in patients with advanced breast cancer pretreated with anthracyclines: a randomised phase III trial of Turkish Oncology Group

Our objective was to determine whether oral etoposide and cisplatin combination (EoP) is superior to paclitaxel in the treatment of advanced breast cancer (ABC) patients pretreated with anthracyclines. From December 1997 to August 2003, 201 patients were randomised, 100 to EoP and 101 to paclitaxel arms. Four patients in each arm were ineligible. The doses of etoposide and cisplatin were 50 mg p.o. twice a day for 7 days and 70 mg m⁻² intravenously (i.v.) on day 1, respectively, and it was 175 mg m⁻² on day 1 for paclitaxel. Both treatments were repeated every 3 weeks. A median of four cycles of study treatment was given in both arms. The response rate obtained in the EoP arm was significantly higher (36.3 vs 22.2%; P=0.038). Median response duration was longer for the EoP arm (7 vs 4 months) (P=0.132). Also, time to progression was significantly in favour of the EoP arm (5.5 vs 3.9 months; P=0.003). Median overall survival was again significantly longer in the EoP arm (14 vs 9.5 months; P=0.039). Toxicity profile of both groups was similar. Two patients in each arm were lost due to febrile neutropenia. The observed activity and acceptable toxicity of EoP endorses the employment of this combination in the treatment of ABC following anthracyclines.

Evidence-based use of neoadjuvant taxane in operable and inoperable breast cancer

Neoadjuvant chemotherapy (NC) is standard therapy for patients with locally advanced breast cancer and is increasingly used for early-stage operable disease. The aim of NC is a pathological complete response (pCR) in the breast and axillary lymph nodes, which is the best predictor of improved outcome and prolonged survival. The taxanes docetaxel and paclitaxel are potent agents in breast cancer management, with promising single-agent activity and acceptable tolerability in the neoadjuvant setting. In this review of the taxanes as NC for operable and inoperable breast cancer, we include all fully published Phase II-III studies enrolling > or =30 patients. Current evidence suggests that the sequential administration of taxane- and anthracycline-based therapy may be superior to concomitant administration. Indeed, until the recent Phase III Aberdeen study (n = 162), it was uncertain whether NC could prolong survival. In this study, sequential docetaxel after anthracycline-based NC significantly enhanced the clinical response rate and pathological complete response, and yielded a significant 3-year survival advantage, versus anthracycline-based NC alone. Recently, the Phase III National Surgical Adjuvant Breast and Bowel Project (NSABP) trial B27 trial (n = 2411) showed that sequential docetaxel after doxorubicin-cyclophosphamide significantly increased both clinical and pathological response rates for operable breast cancer, with the benefit evident in both estrogen receptor-positive and estrogen receptor-negative patients. This apparent superiority of a sequential anthracycline-taxane regimen is limited to docetaxel, with no similar Phase III trials of paclitaxel versus a non-taxane-based comparator having been conducted to date. In conclusion, current evidence supports the inclusion of a taxane in NC schedules for patients with large and locally advanced breast cancer.

Facts and Controversies in Systemic Treatment of Metastatic Breast Cancer

The management of metastatic breast cancer remains an important and controversial issue. The systemic therapy, comprising endocrine, cytotoxic and biological agents, can be administered sequentially or in combination. Few drugs or combinations provide a significant improvement in survival and, therefore, in the great majority of cases, treatment is given with a palliative intent. With the exception of first-line therapy, for which general agreement exists, currently there is no consensual standard of care. This review will summarize the current knowledge and outline the controversial issues related to systemic therapy of metastatic breast cancer, with emphasis on treatment tailoring. The potential role of tumor molecular profile(s) in the selection of patients that could benefit the most from each strategy/agent will be discussed.

Docetaxel and paclitaxel in the treatment of breast cancer: a review of clinical experience

In the 10 years since their initial licensing in Europe, the taxanes, paclitaxel and docetaxel, have emerged as fundamental drugs in the treatment of breast cancer. Clinically meaningful benefits were first shown in the metastatic setting, and large-scale exploration of their roles in the adjuvant therapy of early-stage disease is ongoing. Benefits have been seen in the neoadjuvant setting as well, mainly with docetaxel. This paper reviews the current roles of the taxanes in the treatment of metastatic and early-stage breast cancer. Also addressed are outstanding issues involving optimal dosing and sequencing, as well as a discussion of the relative merits of each agent in this setting. Clinicians should choose a taxane-based regimen for their patients with breast cancer based on consideration of the pharmacokinetics, clinical activity, and dosing schedule that best meets the patients' needs. At the current time, the pharmacokinetic profile, consistent positive clinical results, and convenience of an intermittent, short-infusion schedule have made docetaxel the preferred taxane for many clinicians treating patients with breast cancer.

Chemotherapy for metastatic breast cancer

PURPOSE OF REVIEW

This review is intended to summarize the most up-to-date information in the field of chemotherapy for advanced breast cancer.

RECENT FINDINGS

During the past year, the literature on chemotherapy for metastatic breast cancer has focused on three main areas of interest: the development of new cytotoxic agents with most studies addressing the taxane-pretreated population; the evaluation of new combination regimens, mainly incorporating a taxane; and the development of new trastuzumab-cytotoxic-agent combinations in the HER-2-positive population. In addition, interesting data regarding combination versus sequential single-agent chemotherapy and the optimal duration of chemotherapy have been published.

SUMMARY

Interesting new drugs have faced phase II development. Randomized trials will define their role in the daily management of metastatic breast cancer. New combination regimens, generally incorporating a taxane, improve short-term efficacy in comparison with standard anthracycline-based combinations or single-agent chemotherapy, but at the cost of increased toxicity. Trastuzumab can be safely combined with several cytotoxic agents.