Identification of the highest dose of docetaxel associable with active doses of epirubicin. Results from a dose-finding study in advanced breast cancer patients

Revisiting Dosing Regimen Using Pharmacokinetic/Pharmacodynamic Mathematical Modeling: Densification and Intensification of Combination Cancer Therapy

Controlling effects of drugs administered in combination is particularly challenging with a densified regimen because of life-threatening hematological toxicities. We have developed a mathematical model to optimize drug dosing regimens and to redesign the dose intensification-dose escalation process, using densified cycles of combined anticancer drugs. A generic mathematical model was developed to describe the main components of the real process, including pharmacokinetics, safety and efficacy pharmacodynamics, and non-hematological toxicity risk. This model allowed for computing the distribution of the total drug amount of each drug in combination, for each escalation dose level, in order to minimize the average tumor mass for each cycle. This was achieved while complying with absolute neutrophil count clinical constraints and without exceeding a fixed risk of non-hematological dose-limiting toxicity. The innovative part of this work was the development of densifying and intensifying designs in a unified procedure. This model enabled us to determine the appropriate regimen in a pilot phase I/II study in metastatic breast patients for a 2-week-cycle treatment of docetaxel plus epirubicin doublet, and to propose a new dose-ranging process. In addition to the present application, this method can be further used to achieve optimization of any combination therapy, thus improving the efficacy versus toxicity balance of such a regimen.

Revisiting dosing regimen using PK/PD modeling: the MODEL1 phase I/II trial of docetaxel plus epirubicin in metastatic breast cancer patients

The MODEL1 trial is the first model-driven phase I/II dose-escalation study of densified docetaxel plus epirubicin administration in metastatic breast cancer patients, a regimen previously known to induce unacceptable life-threatening toxicities. The primary objective was to determine the maximum tolerated dose of this densified regimen. Study of the efficacy was a secondary objective. Her2-negative, hormone-resistant metastatic breast cancer patients were treated with escalating doses of docetaxel plus epirubicin every 2 weeks for six cycles with granulocyte colony stimulating factor support. A total of 16 patients were treated with total doses ranging from 85 to 110 mg of docetaxel plus epirubicin per cycle. Dose escalation was controlled by a non-hematological toxicity model. Dose densification was guided by a model of neutrophil kinetics, able to optimize docetaxel plus epirubicin dosing with respect to pre-defined acceptable levels of hematological toxicity while ensuring maximal efficacy. The densified treatment was safe since hematological toxicity was much lower compared to previous findings, and other adverse events were consistent with those observed with this regimen. The maximal tolerated dose was 100 mg given every 2 weeks. The response rate was 45 %; median progression-free survival was 10.4 months, whereas 54.6 months of median overall survival was achieved. The optimized docetaxel plus epirubicin dosing regimen led to fewer toxicities associated with higher efficacy as compared with standard or empirical densified dosing. This study suggests that model-driven dosage adjustment can lead to improved efficacy-toxicity balance in patients with cancer when several anticancer drugs are combined.

Sequential docetaxel as adjuvant chemotherapy for node-positive or/and T3 or T4 breast cancer: clinical outcome (Mansoura University)

This trial compared 6 cycles of fluorouracil, epirubicin, and cyclophosphamide (FEC) with a sequential regimen of 3 cycles of FEC followed by 3 cycles of docetaxel (FEC-D) as adjuvant treatment for women with node-positive or/and T3 or T4 breast cancer. Between January 2006 and January 2010, 657 patients with operable breast cancer were randomly assigned to either FEC every 21 days for 6 cycles, or 3 cycles of FEC followed by 3 cycles of docetaxel, both given every 21 days. Radiotherapy was mandatory for all patients who had undergone breast conserving surgery. Radiation to the chest wall, supraclavicular area, was recommended following mastectomy. Hormone-receptor-positive patients received tamoxifen for 5 years after chemotherapy. The primary end point was 5-year disease-free survival (DFS). Median follow-up was 61 months. Five-year DFS rates were 74 % with FEC and 78 % with FEC-D (P = 0.013). Multivariate analysis adjusted for prognostic factors showed a 17 % reduction in the relative risk of relapse with FEC-D. Five-year overall survival rates were 85 % with FEC and 89.4 % with FEC-D, demonstrating a 27 % reduction in the relative risk of death (P = 0.014). The incidence of grade 3-4 neutropenia, the need for hematopoietic growth factor, and incidence of nausea/vomiting were higher with FEC. Docetaxel was associated with more febrile neutropenia, stomatitis, edema, and nail disorders. Though rare overall, there were fewer cardiac events after FEC-D, attributable mainly to the lower anthracycline cumulative dose. Sequential adjuvant chemotherapy with FEC followed by docetaxel significantly improves disease-free and overall survival in node-positive or/and T3 or T4 breast cancer patients. Although the magnitude of the benefit observed with FEC-D, differences in the toxicity profiles of FEC and FEC-D may influence the choice of treatment for patients.

Salvage chemotherapy with docetaxel and epirubicin for advanced/metastatic gastric cancer

BACKGROUND

We conducted a phase II study to assess the efficacy and tolerability of docetaxel and epirubicin as salvage chemotherapy in advanced/metastatic gastric cancer patients with documented progression after 5-fluorouracil/platinum-based combination chemotherapy.

METHODS

Docetaxel 75 mg/m(2) and epirubicin 50 mg/m(2) were administered on days 1 and 2, respectively, every 3 weeks. Treatment continued until progression of disease or until a life-threatening adverse event occurred. The primary objectives of this study were to evaluate the safety profile and response rate to this treatment regimen.

RESULTS

Thirty-four patients were enrolled in the study. Twenty-six patients had locally advanced or metastatic disease at the time of diagnosis, and 8 patients had recurrent disease after surgical resection of the primary tumor. A total of 157 chemotherapy cycles were administered. Seven (21.8%) patients had a partial response and 12 (37.5%) patients had stable disease. The median time to progression and overall survival were 4.1 and 13.4 months, respectively. Grade III/IV hematologic toxicities included neutropenia in 16 patients (47%) and febrile neutropenia in 8 patients (24%). Nonhematologic toxicities were rare.

CONCLUSION

A combination of chemotherapy with docetaxel and epirubicin showed moderate activity as salvage treatment in advanced/metastatic gastric cancer, especially in patients who had responded to prior chemotherapy.

Inactivation of NF- B by 3,3'-diindolylmethane contributes to increased apoptosis induced by chemotherapeutic agent in breast cancer cells

Constitutive activation of Akt or nuclear factor-kappaB (NF-kappaB) has been reported to play a role in de novo resistance of cancer cells to chemotherapeutic agents, which is a major cause of treatment failure in cancer chemotherapy. Previous studies have shown that 3,3'-diindolylmethane (DIM), a major in vivo acid-catalyzed condensation product of indole-3-carbinol, is a potent inducer of apoptosis, inhibitor of tumor angiogenesis, and inactivator of Akt/NF-kappaB signaling in breast cancer cells. However, little is known regarding the inactivation of Akt/NF-kappaB that leads to chemosensitization of breast cancer cells to chemotherapeutic agents, such as Taxotere. Therefore, we examined whether the inactivation Akt/NF-kappaB signaling caused by B-DIM could sensitize breast cancer cells to chemotherapeutic agents both in vitro and in vivo. MDA-MB-231 cells were simultaneously treated with 15 to 45 micromol/L B-DIM and 0.5 to 1.0 nmol/L Taxotere for 24 to 72 h. Cell growth inhibition assay, apoptosis assay, electrophoretic mobility shift assay, and Western blotting were done. The combination treatment of 30 micromol/L B-DIM with 1.0 nmol/L Taxotere elicited significantly greater inhibition of cell growth compared with either agent alone. The combination treatment induced greater apoptosis in MDA-MB-231 cells compared with single agents. Moreover, we found that NF-kappaB activity was significantly decreased in cells treated with B-DIM and Taxotere. We also have tested our hypothesis using transfection studies, followed by combination treatment with B-DIM/Taxotere, and found that combination treatment significantly inhibited cell growth and induced apoptosis in MDA-MB-231 breast cancer cells mediated by the inactivation of NF-kappaB, a specific target in vitro and in vivo. These results were also supported by animal experiments, which clearly showed that B-DIM sensitized the breast tumors to Taxotere, which resulted in greater antitumor activity mediated by the inhibition of Akt and NF-kappaB. Collectively, our results clearly suggest that inhibition of Akt/NF-kappaB signaling by B-DIM leads to chemosensitization of breast cancer cells to Taxotere, which may contribute to increased growth inhibition and apoptosis in breast cancer cells. The data obtained from our studies could be a novel breakthrough in cancer therapeutics by using nontoxic agents, such as B-DIM, in combination with other conventional therapeutic agents, such as Taxotere.

Sequential adjuvant epirubicin-based and docetaxel chemotherapy for node-positive breast cancer patients: the FNCLCC PACS 01 Trial

PURPOSE

The PACS 01 trial compared six cycles of fluorouracil, epirubicin, and cyclophosphamide (FEC) with a sequential regimen of three cycles of FEC followed by three cycles of docetaxel (FEC-D) as adjuvant treatment for women with node-positive early breast cancer.

PATIENTS AND METHODS

Between June 1997 and March 2000, 1,999 patients with operable node-positive breast cancer were randomly assigned to either FEC every 21 days for six cycles, or three cycles of FEC followed by three cycles of docetaxel, both given every 21 days. Hormone-receptor-positive patients received tamoxifen for 5 years after chemotherapy. The primary end point was 5-year disease-free survival (DFS).

RESULTS

Median follow-up was 60 months. Five-year DFS rates were 73.2% with FEC and 78.4% with FEC-D (unadjusted P = .011; adjusted P = .012). Multivariate analysis adjusted for prognostic factors showed an 18% reduction in the relative risk of relapse with FEC-D. Five-year overall survival rates were 86.7% with FEC and 90.7% with FEC-D, demonstrating a 27% reduction in the relative risk of death (unadjusted P = .014; adjusted P = .017). The incidence of grade 3 to 4 neutropenia, the need for hematopoietic growth factor, and incidence of nausea/vomiting were higher with FEC. Docetaxel was associated with more febrile neutropenia in the fourth cycle, stomatitis, edema, and nail disorders. Though rare overall, there were fewer cardiac events after FEC-D (P = .03), attributable mainly to the lower anthracycline cumulative dose.

CONCLUSION

Sequential adjuvant chemotherapy with FEC followed by docetaxel significantly improves disease-free and overall survival in node-positive breast cancer patients and has a favorable safety profile.

Multicenter phase II study of trastuzumab in combination with epirubicin and docetaxel as first-line treatment for HER2-overexpressing metastatic breast cancer

The primary objective of study is to evaluate cardiac safety of trastuzumab in combination with epirubicin and docetaxel. HER2-overexpressing metastatic breast cancer patients were enrolled in a two-stage, multicenter phase II trial with weekly trastuzumab (4 and then 2 mg/kg) with epirubicin and docetaxel (either 75 mg/m(2)) on day 1 every 3 weeks. After eight courses of chemotherapy, trastuzumab was continued as a single agent. To assess cardiotoxicity, patients were evaluated for left ventricular ejection fraction (LVEF) at baseline, every two cycles during chemotherapy and trastuzumab, and every 3 months during trastuzumab alone. Cardiotoxicity was defined as signs and/or symptoms of congestive heart failure (CHF) and/or an absolute decrease in LVEF of >or=20 units or a decline to <or=45%. In the first stage of the study, three episodes of cardiotoxicity were observed (two asymptomatic declines of LVEF and one CHF) in 29 patients, and recruitment continued. During follow-up of patients who continued trastuzumab after chemotherapy, seven further cardiologic events occurred (three asymptomatic decline of LVEF and four CHF). Therefore, recruitment was interrupted after the 45th patient. The majority of cardiac events occurred late during trastuzumab alone, half were asymptomatic and all cases of CHF were resolved using cardiac therapy. Complete and partial responses were 20 and 47%, respectively, and the median time to progression was 15.7 months (95% CI, 11.6-19.0 months). In light of the cardiotoxicity experienced during this study, we currently recommend that this combination be used only in controlled clinical trials under vigilant cardiac monitoring.

Dose-finding study of weekly docetaxel, anthracyclines plus fluoropyrimidines as first-line treatment in advanced breast cancer

BACKGROUND

The efficacy and safety of prolonged fluoropyrimidines, either intravenously or orally, prompted their integration with taxanes and anthracyclines in the treatment of advanced breast cancer (ABC). We conducted three subsequent dose-finding studies on first-line chemotherapy in ABC with anthracyclines, either epirubicin (E) or doxorubicin (A), and docetaxel (T), both given on days 1 and 8 every 3 weeks, plus continuous infusion (CI) 5-fluorouracil (F) or capecitabine (X).

PATIENTS AND METHODS

Sixty-two patients (37% dominant visceral disease, 48% locally advanced disease, 45% two or more sites involved), received different doses of T (60--80 mg/m(2)), A (40--50 mg/m(2)) or E (60--90 mg/m(2)) and X (1,650 and 2,000 mg/m(2)), or CI F at a fixed daily dose of 200 mg/m(2). Cardiac function was monitored at baseline and then every four cycles by echocardiography.

RESULTS

The median number of cycles per patient with all regimens was four (range one to eight). Haematological and gastrointestinal toxicity defined the maximum tolerated doses, at T-80/E-90 mg/m(2) with TEF, T-70/A50/X-2,000 mg/m(2) with TAX and T-70/E-80/X-1,650 mg/m(2) with TEX. Two patients treated with TEF developed transient cardiac toxicity (dilatative cardiomyopathy and coronary subtotal stenosis requiring stenting) after cumulative E doses of 400 mg and 1,100 mg/m(2), respectively. Fifty-nine patients were evaluable for response; the overall response rates (ORR) were comparable between regimens (54% with TEF, 71% with TAX and 86% with TEX), with an 81% ORR in 31 patients with locally advanced disease.

CONCLUSIONS

The addition of fluoropyrimidines to weekly, intermittent ET is well tolerated and active in ABC.

Model Describing the Relationship Between Pharmacokinetics and Hematologic Toxicity of the Epirubicin-Docetaxel Regimen in Breast Cancer Patients

Purpose

The aims of the present study were (1) to characterize the pharmacokinetics of both component drugs and (2) to describe the relationship between the pharmacokinetics and the dose-limiting hematologic toxicity for the epirubicin (EPI)/docetaxel (DTX) regimen in breast cancer patients.

Patients and Methods

Forty-four patients with advanced disease received EPI and DTX every 3 weeks for up to nine cycles. The initial doses (EPI/DTX) were 75/70 mg/m2. Based on leukocyte (WBC) and platelet counts, the subsequent doses were, stepwise, either escalated (maximum, 120/100 mg/m2) or reduced (minimum, 40/50 mg/m2). Hematologic toxicity was monitored in all patients, whereas pharmacokinetics was studied in 16 patients. A semiphysiological model, including physiological parameters as well as drug-specific parameters, was used to describe the time course of WBC count following treatment.

Results

In the final pharmacokinetic model, interoccasion variability was estimated to be less than interindividual variability in the clearances for both drugs. The sum of the individual EPI and DTX areas under concentration-time curve correlated stronger to WBC survival fraction than did the corresponding sum of doses. A pharmacokinetic-pharmacodynamic (PK-PD) model with additive effects of EPI and DTX could adequately describe the data.

Conclusion

The final PK-PD model might provide a tool for calculation of WBC time course, and hence, for prediction of nadir day and duration of leukopenia in breast cancer patients treated with the EPI/DTX regimen.

Phase II study of docetaxel in combination with epirubicin and protracted venous infusion 5-fluorouracil (ETF) in patients with recurrent or metastatic breast cancer. A Yorkshire breast cancer research group study

This study was originally designed as a phase I/II study, with a dose escalation of docetaxel in combination with epirubicin 50 mg m⁻² and 5-fluorouracil (5-FU) 200 mg m⁻² day⁻¹. However, as dose escalation was not possible, the study is reported as a phase II study of the combination to assess response and toxicity. A total of 51 patients with locally advanced or metastatic breast cancer were treated on this phase II study, with doses of docetaxel 50 mg m⁻², epirubicin 50 mg m⁻² and infusional 5-FU 200 mg m⁻² day⁻¹ for 21 days. The main toxicity of this combination was neutropenia with 89% of patients having grade 3 and 4 neutropenia, and 39% of patients experiencing febrile neutropenia. Nonhaematological toxicity was mild. The overall response rate in the assessable patients was 64%, with median progression-free survival of 38 weeks, and median survival of 70 weeks. The ETF regimen was found to be toxic, and it was not possible to escalate the dose of docetaxel above the first dose level. This regimen has therefore not been taken any further, but as a development of this a new study is ongoing, combining 3-weekly epirubicin, weekly docetaxel and capecitabine, days 1–14.

Docetaxel plus epirubicin is a highly active, well-tolerated, first-line chemotherapy for metastatic breast cancer: results of a large, multicentre phase II study

PURPOSE

In this multicentre phase II study, the efficacy and safety profile of the combination of docetaxel and epirubicin as first-line chemotherapy for metastatic breast cancer (MBC) were evaluated.

METHODS

Epirubicin (75 mg/m(2)) and docetaxel (75 mg/m(2)) were given intravenously once every 3 weeks for six cycles to 133 patients with MBC.

RESULTS

The overall clinical response rate was 67% (complete and partial responses were 23% and 44%, respectively). The median time to progression was 10.8 months (95% CI 9.7-12.6) and the median overall survival was 19.5 months. Granulocyte colony-stimulating factor support was administered to 32% of patients and in 22% of cycles. Grade 3/4 neutropenia occurred in 35% of patients and febrile neutropenia in 19%. The most frequent grade 3/4 non-haematological toxicities (as percent of patients) were asthenia (6%), vomiting (5%) and nausea (5%). No patients developed congestive heart failure.

CONCLUSIONS

The combination of docetaxel and epirubicin was highly active as first-line treatment for MBC and showed a manageable toxicity profile.

Influence of trastuzumab on epirubicin pharmacokinetics in metastatic breast cancer patients

BACKGROUND

Anthracycline cardiotoxicity is increased by the contemporaneous administration of trastuzumab. The mechanism by which it occurs is as yet unknown. The aim of this study was to evaluate whether trastuzumab modifies the pharmacokinetics of epirubicin and its metabolites.

PATIENTS AND METHODS

Women with HER2-positive metastatic breast cancer were treated with epirubicin 75 mg/m(2) i.v. bolus followed by docetaxel 75 mg/m(2) in a 1-h infusion, every 3 weeks for six cycles, and trastuzumab (once at 4 mg/m(2), then 2 mg/m(2) weekly thereafter) in a 30-min infusion. Epirubicin pharmacokinetic data of seven patients were evaluated at the first cycle of therapy (baseline, with trastuzumab administered 24 h after epirubicin), and at the sixth cycle (i.e. 15 weeks after baseline, with trastuzumab administered immediately before epirubicin).

RESULTS

No pharmacokinetic change in the parent compound epirubicin was detected. The area under the plasma concentration-time curve (AUC(0-24 h)) was 1230 +/- 318 [mean +/- standard deviation (SD)] at the first cycle and 1287 +/- 385 h. micro g/l at the sixth. The mean (+/-SD) maximum plasma concentration (C(max)) and the terminal elimination half-life at the first cycle (1303 +/- 490 micro g/l and 12.5 +/- 3.1 h, respectively) were similar to those obtained at the sixth cycle (1229 +/- 580 micro g/l and 11.5 +/- 2.9 h, respectively). Pharmacokinetic data of epirubicin metabolites evaluated at the first and sixth cycle of chemotherapy were superimposable without any statistical difference.

CONCLUSION

Enhanced anthracycline cardiotoxicity related to trastuzumab administration was not linked to pharmacokinetic interferences with epirubicin and its metabolites.

Capecitabine in combination with docetaxel and epirubicin in patients with previously untreated, advanced breast carcinoma

BACKGROUND

The objective of this study was to evaluate the activity and safety of oral capecitabine in combination with docetaxel and epirubicin (TEX) as first-line treatment for patients with locally advanced/metastatic breast carcinoma.

METHODS

This open-label, Phase II study was conducted at six Italian centers. Treatment consisted of epirubicin, 75 mg/m(2) (intravenous bolus), and docetaxel, 75 mg/m(2) (1-hour infusion), both administered on Day 1, plus oral capecitabine, 1000 mg/m(2) twice daily, on Days 1-14 of each 3-week treatment cycle.

RESULTS

A total of 67 patients received 392 cycles of treatment, with a median of 6 cycles in patients with Stage III disease (n = 34 patients) and a median of 8 cycles in patients with Stage IV disease (n = 33 patients). The objective response rate was 82%, including complete responses in 21% of patients. A greater proportion of patients with Stage III disease achieved tumor responses compared with patients who had Stage IV disease (97% vs. 67%, respectively). Among 34 patients with Stage III disease, pathologic complete responses were confirmed in 10 patients (29%). TEX chemotherapy demonstrated an acceptable safety profile. There was a low incidence of Grade 3 adverse events, and Grade 4 adverse events were particularly rare (4%). The most common Grade 3-4 adverse event was febrile neutropenia, which occurred in 16% of patients.

CONCLUSIONS

TEX combination therapy has important antitumor activity and an acceptable safety profile in this setting. A large, randomized, Phase III trial is ongoing to compare TEX chemotherapy with an epirubicin plus docetaxel regimen in patients with untreated, advanced breast carcinoma.

Phase I and pharmacokinetic study of docetaxel in combination with epirubicin and cyclophosphamide in advanced cancer: dose escalation possible with granulocyte colony-stimulating factor, but not with prophylactic antibiotics

BACKGROUND

The objective of this phase I trial was to determine the maximally tolerated doses of the combination of docetaxel, epirubicin and cyclophosphamide.

PATIENTS AND METHODS

Patients with advanced cancer, World Health Organization (WHO) performance status 0 to 2, who had received up to one prior chemotherapy regimen were treated with docetaxel, epirubicin and cyclophosphamide repeated every 21 days. The cyclophosphamide dose was fixed at 600 mg/m(2) and the dose levels studied were: docetaxel/epirubicin; 60/60, 75/60, 75/75, 75/90, 85/90 and 85/105 mg/m(2). There was provision for the addition of prophylactic ciprofloxacin and granulocyte colony-stimulating factor (G-CSF) in separate steps if dose-limiting toxicity (DLT) was neutropenia related.

RESULTS

Forty-three patients were entered and all were assessable for toxicity. Dose-limiting toxicity, predominantly febrile neutropenia, was surprisingly seen at the first dose level. The addition of prophylactic ciprofloxacin did not permit dose escalation, but dose escalation was possible with the addition of G-CSF. The highest administered dose level with G-CSF was docetaxel 85 mg/m(2) and epirubicin 105 mg/m(2) with DLTs in five of six patients. Treatment was well tolerated in 10 patients treated at the recommended dose level (85/90) with only one patient experiencing DLT. Responses were seen in a range of malignancies including breast and anaplastic thyroid cancers. No significant pharmacokinetic interaction was observed, but a transient increase in epirubicinol plasma concentration occurred during and after docetaxel infusion.

CONCLUSIONS

The recommended dose level of docetaxel 85 mg/m(2), epirubicin 90 mg/m(2) and cyclophosphamide 600 mg/m(2) with G-CSF support has a favorable toxicity profile and is suitable for further investigation in phase II and III trials.

Epirubicin/docetaxel regimen in progressive breast cancer-a phase II study

The purpose of this investigation was to evaluate the efficacy and toxicity of 6 months' treatment with the combination of epirubicin and docetaxel in metastatic breast cancer. Thirty-eight women (mean age 51 years, range 35-72) with metastatic breast cancer were treated with a regimen of epirubicin 75 mg/m and docetaxel 75 mg/m every 3 weeks, given 4 times if progression was seen upon evaluation after 4 courses or 8 times in responding/stable patients. The patients received 285 cycles of combination treatment and two treatments with docetaxel or epirubicin alone. When neutropenia with fever was observed, further cycles were given with dose reduction. The median cumulative docetaxel dose was 462 mg/m (range 199-600) and that of epirubicin 476 mg/m (range 199-740). The overall response rate was 54% (95% CI 37-71), with a median duration of response of 14.8 months (95% CI 8.8-27.8). Median time to progression was 12 months, median survival 26 months. Neutropenia below 0.5 x 10 /l occurred following 113 (39%) of the total of 285 cycles given; 21 patients (55%) were hospitalized for febrile neutropenia. We conclude that dose tailoring is required in treatment with an epirubicin and docetaxel regimen to avoid grade 3/4 adverse effects in a significant number of patients treated for metastatic breast cancer.

Phase I, dose-finding study of capecitabine in combination with docetaxel and epirubicin as first-line chemotherapy for advanced breast cancer

PURPOSE

Capecitabine is an oral fluoropyrimidine with considerable activity and minimal myelosuppression and alopecia. This phase I study evaluated the addition of capecitabine to epirubicin/docetaxel combination therapy as first-line treatment for advanced breast cancer.

PATIENTS AND METHODS

Twenty-three female patients with advanced breast cancer received capecitabine (765-1060 mg/m2 twice daily on days 1-14 of a 3-week treatment cycle) in combination with epirubicin and docetaxel (75 mg/m2 i.v. on day 1).

RESULTS

The maximum tolerated dose of capecitabine was 985 mg/m2 and the principal dose-limiting toxicity was febrile neutropenia. No grade 3/4 anemia or thrombocytopenia occurred. There were no grade 4 non-hematological events and grade 3 events other than alopecia were rare. Alopecia occurred in all patients and treatment cycles, and asthenia occurred in all patients and in 84% of treatment cycles. Other frequent adverse events included nausea, vomiting, fever, paresthesia and elevated transaminase levels. An objective response to treatment was observed in 91% (95% confidence interval 72% to 99%) of patients.

CONCLUSIONS

The addition of capecitabine to docetaxel/epirubicin combination therapy provides a well-tolerated and active first-line chemotherapy regimen in patients with advanced breast cancer, and merits phase II/III evaluation.

Influence of alternate sequences of epirubicin and docetaxel on the pharmacokinetic behaviour of both drugs in advanced breast cancer

BACKGROUND

Previously we observed a pharmacokinetic interference of epirubicin elimination when paclitaxel is given in combination in a sequence-dependent manner (i.e. when paclitaxel is administered as first drug). The aim of this study was to determine whether these sequence-dependent pharmacological effects were also evident when epirubicin was combined with docetaxel.

PATIENTS AND METHODS

Patients who received epirubicin 75 mg/m2 or 90 mg/m2 as an intravenous bolus followed immediately by docetaxel 70 mg/m2 or 80 mg/m2 over a 1-h infusion, or the opposite sequence, every 3 weeks were eligible for this study. The pharmacokinetics of docetaxel, epirubicin and its metabolites were studied at the first and second cycle of treatment. Pharmacokinetic data were normalised to the lower dose of each drug. Toxicity was recorded at nadir and graded according to National Cancer Institute Common Toxicity Criteria.

RESULTS

Twelve consecutive patients, each acting as their own control, entered the study. The sequence of drug administration of docetaxel and epirubicin did not affect the pharmacokinetics of the parent anthracycline. Statistically significant lower glucuronidation metabolism of epirubicin was observed in patients who received docetaxel before epirubicin. The pharmacokinetics of docetaxel were not influenced by the sequence of drug administration. No difference in haematological and non-haematological toxicity was observed in the two sequences of treatment.

CONCLUSIONS

The pharmacokinetics of the parent anthracycline and of docetaxel were similar between the two schemes of treatment. The metabolic variations observed, i.e. differences in the plasma levels of epirubicin glucuronides, seem not to have clinical relevance.