A phase I-II study of bi-weekly paclitaxel as first-line treatment in metastatic breast cancer

Paclitaxel as a first-line chemotherapy for Japanese women with advanced or recurrent breast cancer: a multi-institutional practice-based study by the Kyushu Breast Cancer Study Group (KBC-SG)

BACKGROUND

Anthracycline-containing chemotherapy has represented the standard treatment for advanced breast cancer. However, it is sometimes difficult to continue it because of its cumulative cardiac toxicity, and the benefit of adding anthracyclines to the chemotherapy regimen is confined to HER2-overexpressed breast cancer. A non-anthracycline-based novel therapy is necessary to improve the survival and reduce the toxicity.

METHODS

We evaluated the tumor response and adverse events of a first-line paclitaxel therapy in advanced or recurrent breast cancer in a variety of practice settings. Patients were to receive paclitaxel tri-weekly (175 mg/m(2)), bi-weekly (120 mg/m(2)) or weekly (80 mg/m(2)) until disease progression or toxicity precluded further treatment. Tumor response and toxicities were evaluated.

RESULTS

Thirty-three patients received a total of 191 cycles (median 5, range 2-19). All patients completed at least two cycles. In 30 patients who were evaluable for response, there were 16 overall responses [53%, 95% confidence interval (CI) 34-72%], including 5 complete responses (17%, 95% CI 3-31%). The median progression-free survival and overall survival were 16 (95% CI 9-24) months and 29 (95% CI 24-36) months, respectively. Overall treatment was well tolerated, and no myelosuppression >grade 3 was reported during this study. A grade 3 dyspnea was noted in one patient, but it recovered spontaneously, and subsequent administration of paclitaxel was successfully given with no specific treatment. No other toxicity greater than grade 3 was demonstrated.

CONCLUSION

Paclitaxel as a first-line therapy at this dose and schedule is an effective and well-tolerated treatment regimen in Japanese patients with advanced or recurrent breast cancer.

A phase I combination chemotherapy study of biweekly paclitaxel and S-1 administration in patients with advanced gastric cancer

The aim of the current study was to determine the maximum tolerated dose (MTD) and the dose limiting toxicity (DLT) of a combination of paclitaxel and S-1 in patients with advanced gastric cancer. Fifteen patients were enrolled. The dose for S-1 was set at 80 mg/m2/day (days 1-14), while the dose for paclitaxel increased by 10 mg/m2 for every three patients, with a starting dose of 100 mg/m2 and was given biweekly on day 1 and 15. There was no severe toxicity (grade 4) recorded in patients receiving up to 120 mg/m2 of paclitaxel. Leukopenia/neutrophilia with grade 1 to 3 occurred in six patients up to level 3. At 130 mg/m2 of paclitaxel, grade 4 leukocytopenia and neutropenia events and grade 3 diarrhea developed in one out of three patients. One patient in another group of three patients that were enrolled at level 3, developed grade 4 granulocytopenia with fever (a body temperature higher than 38 degrees C) and grade 3 leukocytopenia. Eight patients, out of a total of 15, showed a partial response, resulting in an objective response rate of 53%. Five patients received gastrectomy. Median survival time was 428 days and the 1 year survival rate was 53%. Biweekly paclitaxel/S-1 combination chemotherapy could be safely used for the treatment of advanced gastric cancer. The recommended doses for a phase II study with paclitaxel and S-1 are 120 mg/m2 and 80 mg/m2, respectively.

Neurotoxicity of taxanes: symptoms and quality of life assessment

Paclitaxel (TXL) and docetaxel (TXT), especially TXL, cause neurotoxicity manifested as polyneuropathy. In clinical practice, detailed knowledge of the symptoms and effect on quality of life (QOL) of neurotoxicity is crucially important both for diagnosis of neuropathy and for management of patients treated with taxanes. In this review, we summarize the symptoms of neurotoxicity caused by taxanes, and highlight the importance of QOL assessment in breast cancer patients treated with taxanes. The most common feature of taxane neurotoxicity is a predominant sensory distal neuropathy, and the incidence and severity of the neuropathic manifestations appear to be related to dose level and cumulative dose. A mixture of paresthesias and dysesthesias is often prominent, and the complaints include burning dysesthesia, numbness, tingling, and shooting pains, typically in a stocking-glove distribution. In contrast to sensory disturbances, motor neuropathy is not well recognized, and is believed to be much less common than sensory neuropathy. Weakness is usually mild, and distal motor neuropathy caused by taxanes rarely affects patients' activities of daily living. The effect of neurotoxicity on QOL is not fully understood, as no study has specifically assessed QOL in terms of neurotoxicity. There is therefore a clear need to collect more detailed data about QOL using well validated, reliable instruments. This will enable us to provide the information that patients require when treatment decisions are being made, and will help in the pursuit of the ameliorative interventions.

Weekly paclitaxel: an effective and well-tolerated treatment in patients with advanced breast cancer

The rationale for dose-dense weekly paclitaxel in the treatment of breast cancer is that more frequent delivery of more moderate doses may achieve greater efficacy than larger doses given less often through more sustained exposure of dividing tumor cells to cytotoxic drugs. Weekly paclitaxel has been used successfully in the treatment of advanced breast cancer, as single-agent therapy, in combination chemotherapy, with radiotherapy and with immunomodulating drugs, such as trastuzumab. Many of the patients in these studies have received previous chemotherapy regimens. Nevertheless, response rates with weekly paclitaxel up to 86% have been achieved with single-agent therapy, up to 87% with combination therapy and up to 100% when combined with radiotherapy. Paclitaxel given weekly together with the humanized monoclonal antibody against HER2, trastuzumab, has shown response rates of 50-82% in patients with aggressive HER2-positive tumors. Paclitaxel is associated with moderate toxicity. Its main dose-limiting toxicities are neutropenia and peripheral neuropathy, but these are generally manageable.

Pharmacodynamics of non-break weekly paclitaxel (Taxol) and pharmacokinetics of Cremophor-EL vehicle: results of a dose-escalation study

We characterized the toxicity and determined the maximum tolerated dose of non-break weekly paclitaxel (Taxol) in chemotherapy-naive cancer patients, and studied pharmacokinetics of the formulation vehicle Cremophor-EL with this schedule. Twenty-three patients with primary refractory solid tumors received weekly paclitaxel at the dose range of 70-200 mg/m2. As dose-limiting toxicity we defined granulocytopenia grade > or =2 causing a treatment delay for more than 2 weeks, or febrile neutropenia or grade >2 organ-specific toxicity. Plasma kinetics of Cremophor-EL were analyzed over the first five courses of treatment. Non-break weekly paclitaxel was feasible at doses up to 110 mg/m2, while granulocytopenia precluded scheduled administration of doses > or =130 mg/m2. Clinically relevant peripheral neurotoxicity tended to occur at around 1500 mg/m2 cumulative dosage at weekly doses > or =110 mg/m2. Detectable Cremophor-EL levels were found in all pre-dose samples, but there was no evidence of accumulation up to the sixth course. Our results, discussed in the light of an overview of published data, suggest that chronic weekly administration of paclitaxel is feasible and with a lack of significant accumulation of Cremophor-EL levels at doses up to 90 mg/m2.