A sequence-dependent combination of docetaxel and vinorelbine: pharmacokinetic interactions.

We studied possible pharmacokinetic interactions between docetaxel (DTX) and vinorelbine (VNR) in patients affected by different types of cancer. Patients with metastatic breast cancer or recurrent head and neck cancer received the following schedules: Protocol A: 11 patients were i.v. infused for 1 h with DTX (80 mg/m2) at once, followed by VNR (25 mg/m2) as slow i.v. bolus; Protocol B: VNR (25 mg/m2) as a slow 10 min i.v. bolus was administered to 12 patients, immediately followed by 1 h i.v. infusion of DTX (80 mg/m2). In both schedules, VNR and DTX plasma concentrations versus time were analysed by HPLC obtaining the corresponding non-compartmental pharmacokinetic parameters. VNR appeared pharmacokinetically affected by the sequential administration of DTX, since with protocol B, Cmax and AUC were significantly higher and clearance lower than in protocol A. Moreover, a significant increase in the VNR plasma level was observed in correspondence with the peak plasma level of DTX. By contrast, Cmax, AUC and clearance of DTX did not vary in the two protocols. Also the number of neutrophils at nadir on day 8 of treatment varied significantly in the two schedules. In conclusion we observed altered pharmacokinetic parameters between protocol A (DTX, VNR) and protocol B (VNR/DTX). In particular, patients following protocol B seemed to be exposed to higher VNR plasma concentration and to higher haematological toxicity.

A preliminary pharmacokinetic study of docetaxel, carboplatin and concurrent radiotherapy for regionally advanced squamous cell carcinoma of the head and neck.

This work investigates the pharmacokinetics and toxicity resulting from the concomitant use of low dose carboplatin (CBCA)/docetaxel (DTX) plus concurrent radiotherapy in patients with head and neck cancer. The study comprised 11 patients with stage III-IV head and neck cancer. All patients received 2 Gy radiotherapy daily, 5 fractions per week, up to a planned total of 70 Gy over 7 weeks. CBCA (AUC 0.4 mg/ml, min/day) was also administrated as 20 min i.v. infusion, starting 1 day before the first radiotherapy fraction. CBCA was administered for 5 consecutive days every 2 weeks (weeks 1, 3, 5 and 7). DTX 30 mg/m2 (1 h i.v. infusion) was given as a single dose on days 10, 24 and 38. CBCA on day 1 and DTX on day 10 were analysed to determine the concentration-time curves during the first 24 h. CBCA Cmax and Cmin in 2-5 days and on day 15 and 29, as well as total plasma platinum on days 2, 3, 4, 5, 29 and 43 were also assayed. By calculating the non-compartmental pharmacokinetic parameters of the two drugs from the available plasma concentrations we found in the first week values similar to those reported in the literature as single agents. In contrast, during subsequent weeks (weeks 3 and 5), a significant and progressive increase of platinum levels was observed. So, it could be assumed that after 2 weeks of CBCA and DTX treatment a bias in dose calculation occurred because the linear relationship between creatinine clearance (used to calculate the expected AUC through the Calvert formula) and CBCA clearance was no longer observed.

Clinical and pharmacokinetic data of a docetaxel-epirubicin combination in metastatic breast cancer.

In order to explore activity and pharmacokinetic data of a docetaxel-epirubicin combination we analyzed a population of 60 metastatic breast cancer patients. All the patients had an ECOG performance status < 3; 41 patients (68%) had visceral metastases as dominant site of disease, including 33% with liver metastases. Three or more involved organs were present in 43% of patients; 35% had received prior hormonotherapy; 10% for metastatic disease. Twenty-five patients (42%) had received prior adjuvant chemotherapy; 15% a CAF regimen. Twenty per cent of patients had less than 12 months disease-free interval. Docetaxel and epirubicin were both given at a dose of 75 mg/m2 i.v. d. 1 every 3 weeks. After a median of six cycles we had 5 CR (8.3%), 40 PR (66.6%), 7 NC (11.6%), and 8 PD (13.3%). Response rates in patients with visceral and liver metastases were 78% and 55% respectively. Premenopausal status, < 1 year disease free survival and > 3 metastatic sites were associated with a lower response rate. After a median follow-up of 19 months (12-36), median disease-free survival is 11 months and median overall survival has not been reached. Grade 4 neutropenia was observed in 75% of courses but with febrile neutropenia in 6.2% of courses only. Non-hematologic toxicity wasn't clinically important. A NYHA class III reversible cardiac failure was observed in one patient (1.6%). The pharmacokinetic evaluation in 16 patients has shown that docetaxel transiently interfered with epirubicin plasma level when docetaxel was administered 1 h after epirubicin.

Docetaxel in combination with epirubicin in metastatic breast cancer: pharmacokinetic interactions.

Epirubicin (75 mg/m2) and docetaxel (75 mg/m2) were administered to 16 patients affected by metastatic breast cancer following two different schedules: (1) docetaxel as infusion administered 1 h after epirubicin administration (schedule A); and (2) docetaxel as infusion immediately (10 min) after the end of epirubicin i.v. bolus administration (schedule B). Experimental non-compartmental analyses such as AUC and Css, were affected very little by the drug combination, irrespective of whether the administration of docetaxel was immediately after the epirubicin bolus (10 min) or delayed (1 h). However, serum levels showed evidence of transient drug interaction: in schedule A, docetaxel infusion was associated with a transient increase of plasma epirubicin in correspondence with Cssmax of docetaxel. Bi-compartmental analysis showed a significant difference in epirubicin clearance between protocols A and B. It is suggested that polysorbate 80, used in minimal amounts to formulate docetaxel, may interfere with epirubicin plasma level.