Etienne Chatelut

Institut Claudius Regaud, Tolosa de Llenguadoc, Midi-Pyrénées, France

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Publications (189)799.72 Total impact

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    ABSTRACT: Background: The purpose of this study was to assess the efficacy and tolerance of induction chemotherapy combining LV5FU2 with increased doses of irinotecan adapted to UGT1A1 genotyping and cetuximab in untreated potentially resectable liver metastases of colorectal cancer. Methods: Twenty-six patients, PS 0-1, with class II hepatic metastases received chemotherapy combining irinotecan 260 mg/m(2) on day 1 for UGT1A1 6/6 and 6/7 genotypes and 220 mg/m(2) for UGT1A1 7/7 genotypes, with leucovorin on day 1, 5FU 400 mg/m(2) bolus on day 1 and continuous 5FU infusion for 46 h, and cetuximab on day 1 (day 1 = day 14). Primary prevention with lenograstim (day 5-9) was given to UGT1A1 6/7 and 7/7 genotypes. The primary endpoint was the response rate (RECIST1.1), and the secondary endpoints were tolerance (NCI-CTC criteria) and R0 resection rate. Results: The average number of cycles per patient was 6 (±1.9). The UGT1A1 genotype was 6/6 in 34.6 %, 6/7 in 53.9 %, and 7/7 in 11.5 % of patients. At 6 cycles, 18 patients (69.2 %) presented a partial response, 5 patients (19.2 %) had stable disease, 2 patients (7.7 %) died independently of chemotherapy, and 1 patient (3.9 %) refused the treatment after 3 cycles. Four patients received 2 more cycles and the cumulative response rate at 8 cycles was 76.9 % (20/26). There was no progression. Among assessable patients (n = 23), the overall response rate was 82.6 % and 21 patients (80.7 %) had a metastasis resection. The most frequent grade 3-4 toxicities were neutropenia (31 %), diarrhea (20.8 %), and anorexia (16.4 %). There were no deaths due to toxicity. Conclusions: High-dose FOLFIRI combined with cetuximab yielded high response rates and enabled complete resection of class II hepatic metastases in most patients. It seemed to be well-tolerated among healthy selected patients thanks to irinotecan dose adaptation according to UGT1A1 pharmacogenomics status. This intensified chemotherapy regimen needs to be confirmed in a randomized, phase III study.
    No preview · Article · Jan 2016 · Annals of Surgical Oncology
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    ABSTRACT: Introduction Pazopanib exhibits wide inter-patient pharmacokinetic variability which may contribute to differences in treatment outcome. Unbound drug concentrations are believed to be more relevant to pharmacological responses than total concentrations. Thus it is desirable to evaluate pazopanib binding on plasma proteins and different factors potentially affecting this process. Methods An equilibrium dialysis method coupled with UPLC-MS/MS assay has been optimized and validated for the determination of pazopanib unbound fraction (fu%) in human plasma. Pazopanib binding in the plasma of healthy volunteers and in isolated protein solutions was investigated. The unbound fraction was determined for 24 cancer patients treated daily with pazopanib. Results We found that pazopanib was extensively bound in human plasma (>99.9 %) with a mean fu% value of 0.0106 ± 0.0013 % at 40 μg/mL. Protein binding was concentration independent over a clinically relevant range of concentrations. In isolated protein solutions, pazopanib at 40 μg/mL was mainly bound to albumin (40 g/L) and to a lesser extent to α1-acid glycoprotein (1 g/L) and low density lipoproteins (1.2 g/L), with a mean fu% of 0.0073 ± 0.0022 %, 0.992 ± 0.44 % and 7.4 ± 1.7 % respectively. Inter-patient variability (CV%) of fu% in cancer patients was limited (27.2 %). A correlation was observed between individual unbound fraction values and albuminemia. Conclusions Pazopanib exhibits extensive binding to plasma proteins in human plasma. Variable albumin concentrations, frequently observed in cancer patients, may affect pazopanib unbound fraction with implications for inter-patient variability in drug efficacy and toxicity.
    No preview · Article · Nov 2015 · Investigational New Drugs
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    ABSTRACT: The goal of our study was to assess the impact of patients' genetic background on their sensitivity to carboplatin/paclitaxel hematotoxicity. Parameters describing sensitivity to neutropenia and to thrombocytopenia of 201 patients were extracted from a previous pharmacokinetic/pharmacodynamics analysis, in order to assess their association with 52 candidates SNPs in 18 genes. Carriers of a T allele of SLCO1B3-rs4149117 were 19% less sensitive to thrombocytopenia than the homozygotes for the G allele (p = 0.00279). Carriers of two copies of the ATG haplotypes of NR1I2-rs1523130, rs3814055 and rs1523127 were 19% less sensitive to thrombocytopenia than those harboring other haplotypes (p = 0.025). Our results revealed the importance of SLCO1B3 and NR1I2 in the sensitivity to carboplatin/paclitaxel thrombocytopenia.
    Full-text · Article · Aug 2015 · Pharmacogenomics
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    ABSTRACT: Despite the growing evidence that dihydropyrimidine dehydrogenase deficiency (DPD encoded by DPYD gene) confers a higher risk of developing severe toxicity, most patients are not screened for DPD deficiency before fluoropyrimidine treatment. We report here the genetic and phenotypic analyses of DPD in a family related to a patient who died after a first cycle of 5-fluorouracil and in 15 additional retrospective patients having a partial DPD deficiency (as measured by plasma dihydrouracil/uracil ratio). The patient with lethal toxicity was found to be a compound heterozygote for two DPYD mutations: a novel 8-bp duplication (c.168_175dupGAATAATT, p.Phe59Ter) and c.1679T>G (Ile560Ser). The patient's dihydrouracil/uracil ratio indicates complete DPD deficiency. The novel mutation was found in 2 members of the patient's family. Deleterious DPYD mutations were identified in 9 out of the 15 patients. The relationship between genotype and dihydrouracil/uracil values in the 22 patients of the present study was significant (p=0.01). This article is protected by copyright. All rights reserved. © 2015 American Society for Clinical Pharmacology and Therapeutics.
    No preview · Article · Aug 2015 · Clinical Pharmacology &#38 Therapeutics
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    Full-text · Dataset · May 2015
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    ABSTRACT: Purpose: Neutropenia is a major dose-limiting side effect of chemotherapy and is closely related to febrile neutropenia which mainly occurs during the first cycle. Our objectives were to establish model-based decision rules from early absolute neutrophil counts (ANC) to anticipate prolonged high grade neutropenia at cycle 1 and to prevent it through delayed granulocyte colony stimulating factor (G-CSF) administration in carboplatin-treated patients. Methods: The decision rules were built from Monte Carlo simulations performed with a previously published semi-mechanistic model describing ANC time-course in carboplatin-treated patients with or without concomitant G-CSF therapy. Results: ANC measured at day 0 (D0, baseline), D4 and D5 were good predictors of prolonged high grade neutropenia at cycle 1. Pegfilgrastim administration on D5 was as effective as the conventional pegfilgrastim administration on D1 but none avoided prolonged high grade neutropenia in all patients. Additional decision rules were thus derived, using the same ANC combination, to identify patients for whom G-CSF was beneficial. All decision rules showed good performances (sensitivity/specificity). Conclusion: We propose an innovative approach to guide oncologist in their clinical practice. The next step is to perform prospective studies to implement, validate and possibly refine the proposed decision rules.
    Full-text · Article · Sep 2014 · Pharmaceutical Research
  • Cécile Arellano · Ben Allal · Anwar Goubaa · Henri Roché · Etienne Chatelut
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    ABSTRACT: A selective and accurate analytical method is needed to quantify tamoxifen and its phase I metabolites in a prospective clinical protocol, for evaluation of pharmacokinetic parameters of tamoxifen and its metabolites in adjuvant treatment of breast cancer. The selectivity of the analytical method is a fundamental criteria to allow the quantification of the main active metabolites (Z)-isomers from (Z)'-isomers. An UPLC-MS/MS method was developed and validated for the quantification of (Z)-tamoxifen, (Z)-endoxifen, (E)-endoxifen, Z'-endoxifen, (Z)'-endoxifen, (Z)-4-hydroxytamoxifen, (Z)-4'-hydroxytamoxifen, N-desmethyl tamoxifen, and tamoxifen-N-oxide. The validation range was set between 0.5ng/mL and 125ng/mL for 4-hydroxytamoxifen and endoxifen isomers, and between 12.5ng/mL and 300ng/mL for tamoxifen, tamoxifen N-desmethyl and tamoxifen-N-oxide. The application to patient plasma samples was performed.
    No preview · Article · Aug 2014 · Journal of Pharmaceutical and Biomedical Analysis
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    ABSTRACT: Most of oral targeted therapies are tyrosine kinase inhibitors (TKIs). Oral administration generates a complex step in the pharmacokinetics (PK) of these drugs. Inter-individual PK variability is often large and variability observed in response is influenced not only by the genetic heterogeneity of drug targets, but also by the pharmacogenetic background of the patient (e.g. cytochome P450 and ABC transporter polymorphisms), patient characteristics such as adherence to treatment and environmental factors (drug–drug interactions). Retrospective studies have shown that targeted drug exposure, reflected in the area under the plasma concentration–time curve (AUC) correlates with treatment response (efficacy/toxicity) in various cancers. Nevertheless levels of evidence for therapeutic drug monitoring (TDM) are however heterogeneous among these agents and TDM is still uncommon for the majority of them. Evidence for imatinib currently exists, others are emerging for compounds including nilotinib, dasatinib, erlotinib, sunitinib, sorafenib and mammalian target of rapamycin (mTOR) inhibitors. Applications for TDM during oral targeted therapies may best be reserved for particular situations including lack of therapeutic response, severe or unexpected toxicities, anticipated drug–drug interactions and/or concerns over adherence treatment. Interpatient PK variability observed with monoclonal antibodies (mAbs) is comparable or slightly lower to that observed with TKIs. There are still few data with these agents in favour of TDM approaches, even if data showed encouraging results with rituximab, cetuximab and bevacizumab. At this time, TDM of mAbs is not yet supported by scientific evidence. Considerable effort should be made for targeted therapies to better define concentration–effect relationships and to perform comparative randomised trials of classic dosing versus pharmacokinetically-guided adaptive dosing.
    No preview · Article · Aug 2014 · European Journal of Cancer
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    ABSTRACT: Purpose: First, to evaluate the peritoneal (IP), plasma ultrafiltrated (UF) and protein-bound (B) pharmacokinetics (PK) of oxaliplatin after intraperitoneal hyperthermic chemoperfusion (HIPEC) following cytoreductive surgery. Second, to evaluate the relationship between oxaliplatin exposure and observed toxicity. Methods: IP, UF, and B concentrations from 75 patients treated by 30-min oxaliplatin-based HIPEC procedures were analysed according to a pharmacokinetic modelling approach using NONMEM. Oxaliplatin was administered in a 5 % dextrose solution (2 L/m(2)) at 360 (n = 58) or 460 mg/m(2) (n = 17). The most frequently observed toxicities were related to the peritoneal, systemic exposures and to the parameters corresponding to the oxaliplatin absorption from peritoneal cavity into plasma. Results: IP (n = 536), UF (n = 669) and B (n = 661) concentrations were simultaneously described according to a five-compartment PK model with irreversible nonlinear binding from UF to B according to a Michaelis-Menten equation. The mean (±SD) maximum fraction of dose absorbed and elimination half-life from the peritoneum was 53.7 % (±8.5) and 0.49 h (±0.1), respectively. The mean (±SD) ratio AUC(IP)/AUC(UF) was 5.3 (±2) confirming the pharmacokinetic advantage of the procedure. Haemoperitoneum (22.7 %), neuropathy (18.7 %), grade 3/4 thrombocytopenia (13.3 %) were the most frequently reported toxicities. AUC(UF) accounts for approximately 12 % of the variation in the maximum percentage of platelet decrease (r = 0.35, p = 0.002). Thrombocytopenia was correlated with higher AUCUF, partly dependent on the extent and rate of oxaliplatin absorption. Conclusions: Despite a common dose administered, variability in peritoneal and systemic oxaliplatin exposures are observed, leading to differences in haematological toxicity between patients.
    No preview · Article · Jul 2014 · Cancer Chemotherapy and Pharmacology
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    ABSTRACT: Background: In the clinical development of oncology drugs, the recommended dose is usually determined using a 3 + 3 dose-escalation study design. However, this phase I design does not always adequately describe dose-toxicity relationships. Methods: 125 patients, with either solid tumours or lymphoma, were included in the study and 1217 platelet counts were available over three treatment cycles. The data was used to build a population pharmacokinetic/pharmacodynamic (PKPD) model using a sequential modeling approach. Model-derived Recommended Doses (MDRD) of abexinostat (a Histone Deacetylase Inhibitor) were determined from simulations of different administration schedules, and the higher bound for the probability of reaching these MDRD with a 3 + 3 design were obtained. Results: The PKPD model developed adequately described platelet kinetics in both patient populations with the inclusion of two platelet baseline counts and a disease progression component for patients with lymphoma. Simulation results demonstrated that abexinostat administration during the first 4 days of each week in a 3-week cycle led to a higher MDRD compared to the other administration schedules tested, with a maximum probability of 40 % of reaching these MDRDs using a 3 + 3 design. Conclusions: The PKPD model was able to predict thrombocytopenia following abexinostat administration in both patient populations. A model-based approach to determine the recommended dose in phase I trials is preferable due to the imprecision of the 3 + 3 design.
    No preview · Article · May 2014 · Investigational New Drugs
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    ABSTRACT: Most anticancer drugs are characterised by a steep dose-response relationship and narrow therapeutic window. Inter-individual pharmacokinetic (PK) variability is often substantial. The most relevant PK parameter for cytotoxic drugs is the area under the plasma concentration versus time curve (AUC). Thus it is somewhat surprising that therapeutic drug monitoring (TDM) is still uncommon for the majority of agents. Goals of the review were to assess the rationale for more widely used TDM of cytotoxics in oncology. There are several reasons why TDM has never been fully implemented into daily oncology practice. These include difficulties in establishing appropriate concentration target ranges, common use of combination chemotherapies for many tumour types, analytical challenges with prodrugs, intracellular compounds, the paucity of published data from pharmacological trials and 'Day1=Day21' administration schedules. There are some specific situations for which these limitations are overcome, including high dose methotrexate, 5-fluorouracil infusion, mitotane and some high dose chemotherapy regimens. TDM in paediatric oncology represents an important challenge. Established TDM approaches includes the widely used anticancer agents carboplatin, busulfan and methotrexate, with 13-cis-retinoic acid also recently of interest. Considerable effort should be made to better define concentration-effect relationships and to utilise tools such as population PK/PD models and comparative randomised trials of classic dosing versus pharmacokinetically guided adaptive dosing. There is an important heterogeneity among clinical practices and a strong need to promote TDM guidelines among the oncological community.
    Full-text · Article · May 2014 · European journal of cancer (Oxford, England: 1990)
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    ABSTRACT: Therapeutic drug monitoring (TDM) can be defined as the measurement of drug in biological samples to individualise treatment by adapting drug dose to improve efficacy and/or reduce toxicity. The cytotoxic drugs are characterised by steep dose-response relationships and narrow therapeutic windows. Inter-individual pharmacokinetic (PK) variability is often substantial. There are, however, a multitude of reasons why TDM has never been fully implemented in daily oncology practice. These include difficulties in establishing appropriate concentration target, common use of combination chemotherapies and the paucity of published data from pharmacological trials. The situation is different with targeted therapies. The large interindividual PK variability is influenced by the pharmacogenetic background of the patient (e.g. cytochrome P450 and ABC transporters polymorphisms), patient characteristics such as adherence to treatment and environmental factors (drug-drug interactions). Retrospective studies have shown that targeted drug exposure correlates with treatment response in various cancers. Evidence for imatinib currently exists, others are emerging for compounds including nilotinib, dasatinib, erlotinib, sunitinib, sorafenib and mammalian target of rapamycin (mTOR) inhibitors. Applications for TDM during oral targeted therapies may best be reserved for particular situations including lack of therapeutic response, severe or unexpected toxicities, anticipated drug-drug interactions and concerns over adherence treatment. There are still few data with monoclonal antibodies (mAbs) in favour of TDM approaches, even if data showed encouraging results with rituximab and cetuximab. TDM of mAbs is not yet supported by scientific evidence. Considerable effort should be made for targeted therapies to better define concentration-effect relationships and to perform comparative randomised trials of classic dosing versus pharmacokinetically-guided adaptive dosing.
    Full-text · Article · May 2014 · European journal of cancer (Oxford, England: 1990)
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    ABSTRACT: Voriconazole (VOR) is a triazole antifungal used in the curative treatment of invasive fungal infections (IFI) and the prophylactic treatment of opportunistic fungal infections in immunocompromised patients. It is a drug for which therapeutic drug monitoring (TDM) is highly recommended. In order to determine the best TDM marker, the pharmacologically active form of the drug, represented by the unbound plasma concentration (Cu) and fraction (fu), has been studied using a method based on ultrafiltration and ultra performance liquid chromatography. As albumin is a likely factor inducing fluctuations in fu, the correlation between albumin levels and fu was carried out. Similarly, correlations between trough plasma concentrations (total concentration (Ct) and Cu) and both efficacy and safety markers were determined. Efficacy evaluation was based on monitoring fungal antigens and cultures, while safety was monitored by measuring bilirubin levels. In vitro, using blank human plasma, the mean fu was determined at 32.3 ± 5.5% while in patients' plasmas treated with VOR, the median (5-95 percentiles) of the unbound VOR fraction was 22.95 % (14.95 - 38.42 %). A high correlation was found (rho=0.956, p<0.001) between Ct and Cu, though there was no correlation between serum albumin levels and fu, except for some patients with severe hypoalbuminemia (< 25 g/L). Based on efficacy/safety correlations, a therapeutic window has been defined ranging from 4.5 to 6.5 mg/L and 1.5 and 2.0 mg/L for trough Ct and Cu, respectively. For the first time, the relevance of new pharmacokinetic parameters such as Cu and fu have been explored and discussed, and our results support the current TDM protocol for VOR.
    Full-text · Article · May 2014 · Therapeutic drug monitoring
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    ABSTRACT: A combination of monoclonal antibody that binds and inhibits effects induced by vascular endothelial growth factor and tyrosine kinase inhibitor of vascular endothelial growth factor receptor represents a promising concept to block pathological angiogenesis completely. A phase I study combining daily oral pazopanib and bevacizumab (given iv every 2 weeks) was performed in order to determine the maximum tolerated dose of the two drugs in combination. Pazopanib pharmacokinetics were evaluated to compare pharmacokinetic parameters given alone and those observed on the day of the bevacizumab administration. Plasma pazopanib concentrations were obtained in 25 patients treated at two dose levels (400 or 600 mg) at Day 1 (given alone) and Day 15 (the day of the 7.5 mg/kg bevacizumab infusion), and analyzed using the NONMEM program. The apparent oral clearance (CL/F, mean value of 0.60 L/h) presented an inter-individual variability of 40 %, and an inter-occasion of 27 %. A modest but statistically significant decrease in CL/F was observed from Day 1 to Day 15 (-16.4, 95 % confidence interval of -8.5 to -27.2 %). However, trough pazopanib concentrations observed at Day 16 (24 h after the bevacizumab iv infusion) were not significantly higher than those observed just before the beginning of the bevacizumab iv infusion, suggesting that the pharmacokinetic change between Day 1 and Day 15 was not due to an interaction of bevacizumab. Overall, the mean observed concentrations at the maximum tolerated pazopanib dose (600 mg) at both Day 1 and Day 15 were higher than those observed at 800 mg once daily level (corresponding to the recommended dose when given alone) during the first-in-man phase 1 study of pazopanib in monochemotherapy. This first population pharmacokinetic analysis of pazopanib shows that inter-individual and inter-study pharmacokinetic variability emphasize the need for further evaluation of therapeutic drug monitoring for pazopanib as suggested for other tyrosine kinase inhibitors.
    No preview · Article · Apr 2014 · Cancer Chemotherapy and Pharmacology
  • E Chatelut · F Puisset

    No preview · Article · Apr 2014 · Clinical Pharmacology &#38 Therapeutics
  • M. -N. Paludetto · E. Chatelut
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    ABSTRACT: L’irinotécan et le cisplatine sont deux médicaments anticancéreux dont les effets indésirables fréquents et sévères — toxicité hématologique et digestive pour l’irinotécan, ototoxicité pour le cisplatine — présentent une importante variabilité interindividuelle d’origine en partie génétique. Différentes études ont été mises en place pour identifier les déterminants génétiques de ces toxicités afin de prédire le risque de survenue d’effets indésirables et adapter le traitement en fonction du niveau de risque. Pour l’irinotécan, des recommandations de dose commencent à émerger des nombreux travaux réalisés sur les polymorphismes de l’UDP-glucuronosyl-transférase 1A1 (UGT1A1), principale enzyme impliquée dans la détoxification du métabolite actif de l’irinotécan, le SN-38. La découverte récente du rôle d’autres enzymes (notamment de la même sous-famille UGT1A) et transporteurs (en particulier de la superfamille ABC, ATP Binding Cassette) intervenant dans la pharmacocinétique de l’irinotécan risque de complexifier l’élaboration de telles recommandations. Pour le cisplatine, la détermination des gènes d’intérêt est encore en cours, car les résultats des différentes études restent controversés. Plusieurs gènes impliqués dans les processus intracellulaires de l’ototoxicité ont été évoqués, tels que les gènes des glutathions Stransférases (GST), de la mégaline, de la thiopurine méthyltransférase (TPMT), de la catéchol O-méthyltransférase (COMT) et du transporteur ABCC3, ces trois derniers ayant été intégrés dans un modèle de prédiction de l’ototoxicité. Pour l’irinotécan comme pour le cisplatine, des études complémentaires sont donc encore nécessaires pour atteindre une individualisation complète du traitement.
    No preview · Article · Feb 2014 · Oncologie
  • Florent Puisset · Antonin Schmitt · Etienne Chatelut
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    ABSTRACT: Platinum compounds represent a pharmacological class essential for the treatment of certain types of cancer. Cisplatin, carboplatin, and oxaliplatin, share some physiochemical and pharmacological properties, in particular the ability to form DNA adducts. Carboplatin may be considered as an analog of cisplatin, but its pharmacokinetic properties, side-effects, and intrinsic activity are significantly different from those of cisplatin. The choice of one of these two compounds may be made rationally based on the individual patient's characteristics.
    No preview · Article · Jan 2014 · Anticancer research
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    ABSTRACT: Therapeutic drug monitoring (TDM) can be defined as the measurement of drug in biological samples to individualise treatment by adapting drug dose to improve efficacy and/or reduce toxicity. The cytotoxic drugs are characterised by steep dose–response relationships and narrow therapeutic windows. Inter-individual pharmacokinetic (PK) variability is often substantial. There are, however, a multitude of reasons why TDM has never been fully implemented in daily oncology practice. These include difficulties in establishing appropriate concentration target, common use of combination chemotherapies and the paucity of published data from pharmacological trials. The situation is different with targeted therapies. The large interindividual PK variability is influenced by the pharmacogenetic background of the patient (e.g. cytochrome P450 and ABC transporters polymorphisms), patient characteristics such as adherence to treatment and environmental factors (drug–drug interactions). Retrospective studies have shown that targeted drug exposure correlates with treatment response in various cancers. Evidence for imatinib currently exists, others are emerging for compounds including nilotinib, dasatinib, erlotinib, sunitinib, sorafenib and mammalian target of rapamycin (mTOR) inhibitors. Applications for TDM during oral targeted therapies may best be reserved for particular situations including lack of therapeutic response, severe or unexpected toxicities, anticipated drug–drug interactions and concerns over adherence treatment. There are still few data with monoclonal antibodies (mAbs) in favour of TDM approaches, even if data showed encouraging results with rituximab and cetuximab. TDM of mAbs is not yet supported by scientific evidence. Considerable effort should be made for targeted therapies to better define concentration–effect relationships and to perform comparative randomised trials of classic dosing versus pharmacokinetically-guided adaptive dosing.
    No preview · Article · Jan 2014
  • [Show abstract] [Hide abstract]
    ABSTRACT: Most anticancer drugs are characterised by a steep dose–response relationship and narrow therapeutic window. Inter-individual pharmacokinetic (PK) variability is often substantial. The most relevant PK parameter for cytotoxic drugs is the area under the plasma concentration versus time curve (AUC). Thus it is somewhat surprising that therapeutic drug monitoring (TDM) is still uncommon for the majority of agents. Goals of the review were to assess the rationale for more widely used TDM of cytotoxics in oncology. There are several reasons why TDM has never been fully implemented into daily oncology practice. These include difficulties in establishing appropriate concentration target ranges, common use of combination chemotherapies for many tumour types, analytical challenges with prodrugs, intracellular compounds, the paucity of published data from pharmacological trials and ‘Day1 = Day21’ administration schedules. There are some specific situations for which these limitations are overcome, including high dose methotrexate, 5-fluorouracil infusion, mitotane and some high dose chemotherapy regimens. TDM in paediatric oncology represents an important challenge. Established TDM approaches includes the widely used anticancer agents carboplatin, busulfan and methotrexate, with 13-cis-retinoic acid also recently of interest. Considerable effort should be made to better define concentration–effect relationships and to utilise tools such as population PK/PD models and comparative randomised trials of classic dosing versus pharmacokinetically guided adaptive dosing. There is an important heterogeneity among clinical practices and a strong need to promote TDM guidelines among the oncological community.
    No preview · Article · Jan 2014
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    ABSTRACT: We describe here the case of a 60-year old male patient treated for an extensive local progression of a pleiomorphic sarcoma on the right tibial crest with second-line trabectedin. Two cycles were administrated before a major liver toxicity was retrieved, with both cytolytic and cholestatic hepatitis quickly associated with irreversible jaundice. The radiological, histological, chemistry and pharmacogenetic investigations led us to diagnose chronic hepatobiliary toxicity with portal fibrosis, cholangiolitis damages and chronic hepatopathy. The patient had a deficient variant genotype of ABCC2 (c.-24TT, c.4488CT and c.4544GA), which has been suggested to play a role in excretion of toxic metabolites of trabectedin. This case report is, to our knowledge, the first description of trabectedin's irreversible liver toxicity in a human patient. Supported by a thorough review of the literature, this hepatitis is thought to have resulted from a multihit process involving genetic variants of ABC proteins and comedication.
    No preview · Article · Sep 2013 · Pharmacogenomics

Publication Stats

4k Citations
799.72 Total Impact Points

Institutions

  • 1991-2015
    • Institut Claudius Regaud
      Tolosa de Llenguadoc, Midi-Pyrénées, France
  • 2007-2014
    • University of Toulouse
      Tolosa de Llenguadoc, Midi-Pyrénées, France
    • Ospedali Riuniti di Bergamo
      Bérgamo, Lombardy, Italy
    • Slotervaartziekenhuis
      Amsterdamo, North Holland, Netherlands
  • 1989-2014
    • Paul Sabatier University - Toulouse III
      • Groupe de Pharmacologie clinique et expérimentale des médicaments anticancéreux - EA 3035
      Tolosa de Llenguadoc, Midi-Pyrénées, France
  • 2009
    • Muséum de Toulouse
      Tolosa de Llenguadoc, Midi-Pyrénées, France
  • 2003
    • Centre Antoine-Lacassagne
      Nice, Provence-Alpes-Côte d'Azur, France
  • 2000
    • University of Aberdeen
      Aberdeen, Scotland, United Kingdom
  • 1995
    • University of Bordeaux
      Burdeos, Aquitaine, France
  • 1993-1994
    • University of California, San Diego
      • Department of Medicine
      San Diego, California, United States