The orally administered P-glycoprotein inhibitor R101933 does not alter the plasma pharmacokinetics of docetaxel (original) (raw)
Related papers
Clinical Cancer Research, 2005
Purpose: The purpose of this study was to investigate the safety and tolerability of MS209, a potent inhibitor of P-glycoprotein, when given in combination with docetaxel and to determine whether MS209 affects docetaxel pharmacokinetics. Experimental design: Patients with advanced solid malignancies were eligible for this phase I trial. Docetaxel as 1-hour infusion was given alone during the first cycle. MS209 was introduced as of cycle 2 and given orally 30 minutes after docetaxel infusion. The dose escalation scheme followed a modified Fibonacci model with six steps (docetaxel, 60-100 mg/m2 and MS209, 300-1,200 mg per body). Results: A total of 30 patients were treated at five dose levels. Dose-limiting toxicities were febrile neutropenia, infection, stomatitis, dysphagia, and fatigue. The maximum tolerated dose was reached at level 5 (docetaxel, 80-MS: 1,200). Pharmacokinetic analysis failed to show a strong pharmacokinetic interaction between the two compounds, but at the highes...
European Journal of Cancer, 2006
Docetaxel Sequence A B S T R A C T The aim of this study was to determine the safety and feasibility profile of paclitaxel (PTX) and docetaxel (DTX) in combination and the pharmacokinetic and pharmacodynamic interaction between these two drugs in two different alternated sequences of administration. The starting dose was PTX (100 mg/m 2 ) as a 3-h IV infusion followed by DTX (50 mg/ m 2 ) as 1-h IV infusion or the alternative sequence in every other patient. The sequence was alternated in the second course in each patient treated. Cycle duration was 21 days. Twenty patients received 103 cycles of treatment through three dose levels. Febrile neutropenia and grade 4 neutropenia lasting longer than 7 days were dose-limiting and defined the toxic dose of DTX (50 mg/m 2 ) and PTX (135 mg/m 2 ) in patients with prior treatment and the recommended dose in patients without prior treatment. Non-hematological toxicities included asthenia, neuropathy, arthralgia/myalgia and stomatitis. Pharmacokinetics of DTX were significantly affected by the sequence. Nadir ANC was more profound when DTX was administered first (P = 0.022). There were one complete response and six partial responses, giving an overall response rate of 35%. DTX (50 mg/m 2 ) followed by PTX (135 mg/m 2 ) can be administered safely and it is an active regimen. The pharmacokinetics of PTX are not influenced by DTX but DTX pharmacokinetics depend on the sequence of administration, which influences its haematological toxicity profile.
Clinical Cancer Research an Official Journal of the American Association For Cancer Research, 2000
Previous studies in mice with disrupted mdr1a P-glycoprotein genes have shown that the oral bioavailability of paclitaxel is very low because of the presence of this drugtransporting protein in the intestinal wall. Additional studies with cyclosporin A have shown that this P-glycoproteininhibiting agent is able to increase the bioavailability of paclitaxel in mouse models and in patients. However, the potential immune-suppressive side effects of cyclosporin A renders this compound less suitable for chronic use in cancer patients. In this paper we present the results obtained with GF120918, an experimental P-glycoprotein inhibitor, on the oral bioavailability of paclitaxel in both wild-type and mdr1ab knockout mice. GF120918 (25 mg/kg) was administered p.o. by gavage 15 min or 2 h before oral or i.v. dosing of paclitaxel, respectively. Paclitaxel plasma levels were quantified by high-performance liquid chromatography. GF120918 increased the plasma values for areas under the concentration-time curve of oral paclitaxel in wild-type mice by 6.6-fold from 408 to 2701 ng โ ml ุ1 โ h. Calculated relative to their respective values for area under the concentrationtime curve after i.v. administration, GF120918 increased the oral bioavailability of paclitaxel in wild-type mice from 8.5 to 40.2%. The plasma pharmacokinetics of paclitaxel in mdr1ab knockout mice was not altered by GF120918, whereas the pharmacokinetics of paclitaxel in wild-type mice receiving GF120918 became comparable with mdr1ab knockout mice. This result indicates that GF120918 at this dose-level selectively and completely blocks P-glycoprotein in the intestines and does not notably interfere in the elimination of paclitaxel by metabolism or other transporters. On the basis of this result, GF120918 has been selected for additional study in humans.
Journal of Chemotherapy, 2013
Paclitaxel (PCT) is a cytotoxic agent with a broad antineoplastic activity. IV formulation of PCT causes hypersensitivity reactions in some patients and oral administration is an alternative to decrease the side effects. PCT is not orally available because of low solubility, lack of intestinal permeability, and efflux by pumps in intestinal wall. PCT solution in cremophor EL: ethanol (100 mg/kg) was administered orally to rats after pre-treatment by mefenamic acid, ibuprofen, verapamil, cyclosporine, and verapamilzibuprofen in individual groups. Ibuprofen presented positive effect on intestinal permeation of PCT. C max and area under the serum concentration versus time curve (AUC) after pre-treatment by ibuprofen was decreased when the oral dose of PCT was decreased to 50 and 25 mg/kg, while dose-blood concentration relationship was nonlinear. Rise in oral bioavailability of PCT after pre-treatment by cyclosporine was lower than ibuprofen. It seems that by using ibuprofen in concomitant with potent P-gp inhibitors before PCT solution, oral delivery of PCT could be promising.
Relationship of systemic exposure to unbound docetaxel and neutropenia
Clinical pharmacology and therapeutics, 2005
Our objective was to evaluate the association between exposure to unbound docetaxel and neutropenia in patients with cancer and to identify factors influencing unbound docetaxel clearance. Docetaxel was administered once every 3 weeks at a dose of 75 mg/m 2 to 49 patients with normal liver function (n = 40, group 1) or mild elevations in liver function test results (n = 9, group 2) or at a dose of 50 mg/m2 to patients with moderate elevations in liver function test results (n = 6, group 3). Pharmacokinetic studies and toxicity assessments were performed during the first cycle of therapy. Total docetaxel concentrations were determined by HPLC and tandem mass spectrometry, and unbound docetaxel fraction was determined by equilibrium dialysis. In patients with normal liver function, unbound docetaxel disposition was characterized by mean (+/-SD) maximum plasma concentration (C max), area under the curve (AUC), and clearance values of 233 +/- 101 ng/mL, 32 +/- 143 ng/mL . h, and 565 +/-...
Comparative Pharmacokinetics of Weekly and Every-Three-Weeks Docetaxel
Clinical Cancer Research, 2004
Purpose: Weekly administration of docetaxel has demonstrated comparable efficacy together with a distinct toxicity profile with reduced myelosuppression, although pharmacokinetic data with weekly regimens are lacking. The comparative pharmacokinetics of docetaxel during weekly and once every 3 weeks (3-weekly) administration schedules were evaluated.
Annals of Oncology, 2002
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.
2011
Purpose: P-glycoprotein (Pgp) antagonists have been difficult to develop because of complex pharmacokinetic interactions and a failure to show meaningful results. Here we report the results of a pharmacokinetic and pharmacodynamic trial using a third-generation, potent, noncompetitive inhibitor of Pgp, tariquidar (XR9576), in combination with docetaxel. Experimental Design: In the first treatment cycle, the pharmacokinetics of docetaxel (40 mg/m) were evaluated after day 1 and day 8 doses, which were administered with or without tariquidar (150 mg). Tc-sestamibi scanning and CD56รพ mononuclear cell rhodamine efflux assays were conducted to assess Pgp inhibition. In subsequent cycles, 75mg/m docetaxel was administered with 150mg tariquidar every 3
Clinical cancer research : an official journal of the American Association for Cancer Research, 2001
P-glycoprotein is an efflux pump for many drugs including doxorubicin and paclitaxel. This study evaluated the coadministration of these drugs with the P-glycoprotein inhibitor valspodar (PSC 833) with the aim of determining: (a) maximum tolerated doses (MTDs) of doxorubicin followed by paclitaxel (DP); (b) the MTD of DP combined with PSC 833 (DPV), without and with filgrastim (G-CSF); and (c) the pharmacokinetic interactions of PSC 833 with doxorubicin and paclitaxel. For the first cycle, patients received doxorubicin as a 15-min infusion followed by paclitaxel as a 1-h infusion. For the second cycle, patients received reduced doses of DP with PSC 833 at 5 mg/kg p.o., four times a day for 12 doses. Thirty-three patients with various refractory malignancies were enrolled and assessable. The MTD of DP without PSC 833 was 35 mg/m(2) doxorubicin and 150 mg/m(2) paclitaxel. The MTD of DPV without G-CSF was 12.5 mg/m(2) doxorubicin and 70 mg/m(2) paclitaxel. The dose-limiting toxicity fo...