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Pascale Jolliet

Publications and source records attributed to Pascale Jolliet.

At least 19 recordsLinked to original sources
PubMed2006

Influence of tenofovir, nevirapine and efavirenz on ritonavir-boosted atazanavir pharmacokinetics in HIV-infected patients.

OBJECTIVE: The influence of nevirapine, efavirenz and tenofovir co-administration on ritonavir-boosted atazanavir pharmacokinetics was investigated in HIV (human immunodeficiency virus)-infected patients. METHODS: A population pharmacokinetic analysis was performed in the context of therapeutic drug monitoring (87 patients, 121 samples). RESULTS: A significant increase of atazanavir clearance (Cl/F) was found when either tenofovir (group B), efavirenz (group C), or nevirapine (group D) were co administered with atazanavir/ritonavir in comparison with patients treated with atazanavir/ritonavir and nucleoside reverse transcriptase inhibitors (group A): 6.24+/-0.36 l h(-1) (group A) versus 7.42+/-0.25 l h(-1) (group B) versus 9.60+/-0.27 l h(-1) (group C) versus 17.53+/-0.57 l h(-1) (group D) (P<0.001). However, the decrease of the mean trough plasma concentration of atazanavir was significant only in group D: 1.02+/-0.86 mg/l (group A) versus 0.21+/-013 mg/l (group D) (P<0.001). CONCLUSION: The increase in atazanavir clearance when it is used in combination with nevirapine, efavirenz and/or tenofovir suggests that therapeutic drug monitoring of atazanavir should be performed in such circumstances.

Adenine↗
PubMed2006

A simple formula for individualising ceftazidime dosage administered by continuous infusion in patients with haematological malignancies.

A formula is proposed for individualising ceftazidime dosage administered by continuous infusion in patients with haematological malignancies. Sixty patients were retrospectively randomised into Group A (n=30) to establish the formula and Group B (n=30) to evaluate this formula. Individual ceftazidime clearances were estimated from the ratio between the rate of infusion and plasma concentration at steady state. In Group A, ceftazidime clearance was significantly correlated with creatinine clearance. From this result, a formula (rate of infusion (g/day)=0.00133x[creatinine clearance (mL/min)]x[target concentration at steady state (mg/L)]) is proposed. This formula provided consistent estimations of ceftazidime plasma concentrations in Group B and should help clinicians to define the optimum ceftazidime dosage, particularly in patients with disturbed renal function.

Adult↗
PubMed2005

A population approach to study the influence of nevirapine administration on lopinavir pharmacokinetics in HIV-1 infected patients.

OBJECTIVE: The influence of nevirapine (NVP) on lopinavir (LPV) pharmacokinetics was investigated by a population analysis based on a non-linear mixed-effect modelling method. METHODS: In this analysis, 95 HIV-1 infected patients were studied [52 treated with LPV/ritonavir (400/100 mg twice a day) plus nucleoside reverse transcriptase inhibitors (group A), 22 patients treated with LPV/ritonavir (533.3/133.3 mg twice a day) plus NVP (group B) and 21 patients treated with LPV/ritonavir (400/100 mg twice a day) plus NVP (group C)]. RESULTS: The apparent clearance of LPV [mean+/-SD: 4.56+/-3.94 l h(-1) (group A) versus 7.14+/-1.77 l h(-1) (group B) versus 7.74+/-1.45 l h(-1) (group C)] was significantly (P <0.001) increased by the presence of NVP in the antiretroviral regimen and the mean trough plasma concentration of LPV was reduced in group C relative to group A [mean+/-SD: 2.23+/-1.35 mg/l versus 5.29+/-2.19 mg/l (P < 0.001)]. CONCLUSION: These results suggest an induction of LPV metabolism by NVP.

Adult↗
PubMed2005

No significant influence of saquinavir hard-gel capsule administration on pharmacokinetics of lopinavir in combination with ritonavir: a population approach.

The influence of saquinavir hard-gel capsules on lopinavir pharmacokinetic parameters was investigated using a population approach. Forty-nine patients infected with human immunodeficiency virus type 1 and treated with lopinavir/ritonavir, nucleoside/nucleotide reverse transcriptase inhibitors plus saquinavir (group A), and 118 patients treated with lopinavir/ritonavir plus nucleoside/nucleotide reverse transcriptase inhibitors (group B) were included in the study. No significant relationship was established between the presence or the daily dosage of saquinavir in the treatment and lopinavir population pharmacokinetic parameters. The values (mean+/-standard deviation) of the individual apparent clearance (5.0+/-1.8 vs. 5.0+/-3.2 L/h), volume of distribution (66.6+/-1.6 vs. 66.8+/-1.9 L), absorption rate constant (0.37+/-0.01 vs. 0.37+/-0.03 hours), and trough plasma concentration (5.5+/-2.3 vs. 5.3+/-1.9 mg/L) of lopinavir are not significantly different between groups A and B. This lack of influence of saquinavir on lopinavir pharmacokinetics makes the use of this combination in salvage therapy easier.

Administration, Oral↗
PubMed2005

Pharmacokinetic evidence for the induction of lopinavir metabolism by efavirenz.

AIMS: The influence of efavirenz on lopinavir pharmacokinetics was investigated using a population approach. METHODS: Forty-five HIV patients treated with lopinavir/ritonavir plus efavirenz (A) and 24 patients treated with lopinavir/ritonavir plus nucleoside/nucleotide reverse transcriptase inhibitors (B) were studied. RESULTS: A relationship (P < 0.01) was established between the elimination rate constant of lopinavir (k(10)) and treatment with efavirenz. Mean k(10) was higher in group A than in group B (0.3838 vs 0.2810 h(-1)) (P < 0.001, 95% confidence interval for difference between means 0.1004, 0.1052). CONCLUSIONS: These results suggest that lopinavir metabolism is induced by efavirenz.

Adult↗
PubMed2004

No relationship between high nevirapine plasma concentration and hepatotoxicity in HIV-1-infected patients naive of antiretroviral treatment or switched from protease inhibitors.

OBJECTIVE: A prospective population pharmacokinetic study of nevirapine (NVP) was performed to test the relationship between hepatotoxicity and NVP trough plasma concentration and to identify which covariates could influence NVP pharmacokinetics. METHODS: All patients [77 HIV-1 (human immunodeficiency virus type 1)-infected patients (128 samples)] were either on first-line antiretroviral therapy or switched from successful therapy containing protease inhibitor. Population pharmacokinetic parameters were estimated by a non-linear mixed-effect modelling method. Hepatotoxicity was evaluated by ASAT (aspartate aminotransferase) plasma level. RESULTS: No correlation was found between high NVP trough plasma concentration and high ASAT level or the increase of ASAT level on NVP therapy. Age and Caucasian race were found to be significant covariates of NVP clearance (Cl/F). Population pharmacokinetic parameters (rate absorption constant=1.04 h(-1); Cl/F=3.31 h(-1); apparent volume of distribution=92 l) are consistent with previous studies. CONCLUSION: High NVP trough plasma concentrations are not correlated with hepatotoxicity in our population. NVP clearance is decreased in the elderly patients, suggesting a potential increase of NVP plasma level and the interest of therapeutic drug monitoring for this population.

Anti-HIV Agents↗
PubMed2003

Evidence for a 5-HT2A receptor mode of action in the anxiolytic-like properties of DOI in mice.

DOI [(+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane] displays a high affinity for the rat 5-HT2A, 5-HT2B and 5-HT2C receptors (pKi 7.3, 7.4 and 7.8, respectively) and acts as an agonist. DOI (0.5-4 mg/kg, i.p. 30 min pre-test) increased the number of punished passages in the mouse four plates test (FPT). The anti-punishment action of DOI (1 mg/kg, i.p. 30 min pre-test) was abolished by prior treatment with the selective 5-HT2A receptor antagonist SR 46949B (0.1 and 1 mg/kg, i.p. 45 min pre-test) but not by the selective 5-HT2C receptor antagonist RS 10-2221 (0.1 and 1 mg/kg, i.p. 45 min pre-test) nor the selective 5-HT2C/2B receptor antagonist SB 206553 (0.1 and 1 mg/kg, i.p. 45 min pre-test). An anxiolytic-like action was also observed for DOI (1 mg/kg) in the elevated plus maze (EPM). The anxiolytic-like action of DOI (1 mg/kg, i.p. 30 min pre-test) was antagonised by pre-treatment with SR 46949B (0.125 and 0.5 mg/kg, i.p. 45 min pre-test) but not by RS 10-2221 (0.1 and 1 mg/kg, i.p. 45 min pre-test) nor SB 206553 (0.1 and 1 mg/kg, i.p. 45 min pre-test). In conclusion, DOI produced an anxiolytic-like profile in the mouse FPT and EPM. These effects are likely to be 5-HT2A receptor mediated.

Animals↗
PubMed2003

Antidepressant-like effects in various mice strains in the forced swimming test.

RATIONALE: Strain differences in mice have been reported in response to drugs in the mouse forced swimming test (FST), even if few antidepressants were examined. OBJECTIVES: The aim of the present study was to investigate the influence of genetic factors, using five antidepressants (imipramine, desipramine, citalopram, paroxetine and bupropion) in the mouse FST, in outbred strains (Swiss, NMRI) and inbred strains (DBA/2, C57BL/6J Rj). Moreover, whole brain levels of dopamine (DA), noradrenaline (NA), serotonin (5-HT) in vehicle treated animals, which were or were not subjected to the FST, were measured by HPLC analysis in an attempt to explain behavioural differences. METHODS: For each antidepressant, a dose range (1-16 mg/kg) was tested in the locomotor apparatus and only non-psychostimulant doses were then tested in the FST in order to detect antidepressant-like activity. RESULTS: No baseline differences among Swiss, NMRI, DBA/2 and C57BL/6J Rj strains were observed in our experiments, allowing the comparison of different antidepressants in each strain. Imipramine (16 mg/kg), desipramine, citalopram (4-16 mg/kg) and paroxetine (8 and 16 mg/kg) treatment decreased the immobility time in the Swiss strain and the size of the effect reached more than 20% for each of these antidepressants. C57BL/6J Rj was the only strain sensitive to bupropion (2 and 4 mg/kg). In the NMRI strain, only paroxetine treatment decreased the immobility time (16 mg/kg). CONCLUSION: Our study showed that drug sensitivity is genotype dependent. FST results have shown that Swiss mice are the most sensitive strain to detect 5-HT and/or NA treatment. The use of DBA/2 inbred mice may be limited, as an absence of antidepressant-like response was observed in the FST. The lack of sensitivity to antidepressant treatment in DBA/2 strains could be due to high DA, NA and 5-HT whole brain concentrations.

Animals↗
PubMed2003

Population pharmacokinetics of ceftazidime in burn patients.

AIM: The aim of this study was to characterize, via a population pharmacokinetic approach, the pharmacokinetics of ceftazidime in burn patients who were not in the acute post-injury phase. METHODS: The development of the pharmacokinetic model was based on data from therapeutic drug monitoring (41 patients, 94 samples). The estimation of population pharmacokinetic parameters and the selection of covariates (age, gender, body weight, size of burn and creatinine plasma concentration) that could affect the pharmacokinetics were performed with a nonlinear mixed effect modelling method. RESULTS: No relationship between covariates and the pharmacokinetic parameters was established with the exception of an inverse-linear relationship between creatinine plasma concentration and ceftazidime total clearance. The total clearance of ceftazidime was 2.72 l h-1[coefficient variation (CV) = 56.3%] and the distribution volume of the central compartment was 0.28 l kg-1 (CV = 13.2%) The transfer rate constants (k12, k 21) between the central and peripheral compartments were 0.06718 h-1 (CV = 87.2%) and 0.001823 h-1 (CV = 82.7%), respectively. From these parameters, the total ceftazidime volume of distribution (10.64 l kg-1) was calculated. CONCLUSION: The population parameters were different from those obtained in a previous study performed in fewer patients and in the early period after burn injury. In our study, the lower ceftazidime clearance could be explained by the relative decrease in ceftazidime elimination in relation to the burn area, and the higher ceftazidime volume of distribution in the presence of interstitial oedema, which could act as a reservoir from which ceftazidime returns slowly to the circulation.

Adult↗
PubMed2003

Population pharmacokinetics of imipenem in burn patients.

The interindividual variability of imipenem pharmacokinetic parameters in burn patients suggest that these parameters have to be estimated with a large number of patients. The aim of this study is (i) to estimate these parameters with a population pharmacokinetic approach, and (ii) to test the influence of factors on pharmacokinetics parameters. Data are provided by therapeutic drug monitoring (n = 47,118 samples) and analysed by a nonlinear mixed effect modelling method. Among the tested covariates (age, gender, body weight, height, size of burn and creatinine plasma level) creatinine plasma level affects imipenem pharmacokinetic parameters substantially. The best fit is obtained with a two-compartment model integrating a linear-inverse relationship between imipenem clearance and creatinine plasma level. The estimates of imipenem clearance (16.37 +/- 0.204 L/h) and of the distribution volume of the central compartment (0.376 +/- 0.039 L/kg) are higher in the population of burn patients than the estimates in healthy subjects. This result is connected with high values of glomerule filtration rate and confirms the interest of therapeutic drug monitoring of imipenem in burn patients and particularly for patients with extreme values of creatinine clearance.

Burns↗
PubMed2002

Improved efficacy of fluoxetine in increasing hippocampal 5-hydroxytryptamine outflow in 5-HT(1B) receptor knock-out mice.

To test for the contribution of the 5-HT(1B) receptor subtype in mediating the effects of fluoxetine, a selective serotonin reuptake inhibitor (SSRI), we used intracerebral in vivo microdialysis in awake, freely moving 5-HT(1B) receptor knock-out mice. We show that a single systemic administration of fluoxetine (1, 5 or 10 mg/kg, i.p.) increased extracellular serotonin levels [5-HT](ext) in the ventral hippocampus and frontal cortex of wild-type and mutant mice. However, in the ventral hippocampus, fluoxetine, at the three doses studied, induced a larger increase in [5-HT](ext) in knock-out than in wild-type mice. In the frontal cortex, the effect of fluoxetine did not differ between the two genotypes. The region-dependent response to fluoxetine described here in mutants confirms data we recently reported for another SSRI, paroxetine. These data suggest that 5-HT(1B) autoreceptors limit the effects of selective serotonin reuptake inhibitors on dialysate 5-HT levels at serotonergic nerve terminals located mainly in the ventral hippocampus. Alternative mechanisms, e.g., changes in 5-HT transporter and/or 5-HT(1A) receptor density in 5-HT(1B) receptor knock-out mice could also explain these findings.

Animals↗
PubMed2002

Evidence from a population pharmacokinetics analysis for a major effect of CYP1A2 activity on inter- and intraindividual variations of clozapine clearance.

Interindividual variations of clozapine clearance could be related to individual CYP1A2 activity. A population approach was used to investigate clozapine pharmacokinetics of multiple doses of clozapine in patients. Clozapine plasma concentrations were obtained in 23 patients from therapeutic drug monitoring (83 samples). CYP1A2 activity was estimated by the norclozapine/clozapine plasma levels ratio and data were processed by a nonlinear mixed-effect modelling method. Different covariates (age, body weight, height, CYP1A2 activity, daily dose of clozapine) were tested but CYP1A2 activity was the single parameter that improved significantly the predictive model. The best fit was obtained by integration of a linear relationship between clozapine clearance and CYP1A2 activity. The findings suggest that (i) CYP1A2 activity is a major factor that determines clozapine clearance and (ii) the norclozapine/clozapine ratio could constitute a valuable measure of the CYP1A2 activity. This ratio can be simply determined in the context of therapeutic drug monitoring and could explain the inter- and intraindividual variation of clozapine plasma levels.

Adult↗
PubMedDate not supplied

[Impacts of the new flunitrazepam regulations on the consumption of hypnotics].

The frequent misuse of flunitrazepam has led the French drug agency (AFSSAPS [Agence française de sécurité sanitaire des produits de santé]) to subject this agent to the regulatory regime for drugs known to produce dependency; this drug may now be prescribed for no more than 14 days, is available only on an "ordonnance sécurisée" (prescribing and dispensing subject to stupefacient regulations), and pharmacists must dispense no more than 7 days' supply. We identified, in a French medical-care database, 738 patients who had received at least one flunitrazepam prescription in January 2001, and monitored the hypnotics delivered to this cohort over a period of 8 months. Sixty-nine percent of the patients had replaced flunitrazepam by another hypnotic without any further change. The most surprising result of our survey was the discovery that nearly half of the selected patients stopped using hypnotics during the review period. Although many hypotheses can be offered to account for this phenomenon, it seems that many consumers halted their consumption of flunitrazepam as a result of the new regulatory regime.

Adult↗
PubMedDate not supplied

[Use of the health insurance database by the centres for evaluation and information on pharmacodependance: examples, interests and future prospects].

In France, the observation and evaluation of drug abuse and dependence associated with pychoactive medications are the responsibility of the National Commission for Narcotics and Psychotropic Drugs. In order to assist this commission, several centres for evaluation and information on pharmacodependence (CEIP) were created throughout in France. Recently, in order to complete their epidemiological tools, several centres have developed another pharmacoepidemiological approach using data for refunded prescriptions obtained from the local and regional French Health Insurance database. This article underlines the potential contribution of the Health Insurance database to improving knowledge of drug use in the real-life conditions based on studies performed by the CEIP. Several examples are given showing the extent of the possibilities (population-based studies, cohort studies, development of misuse indicators). In spite of their limitations (e.g. the difference between consumption and delivery), these examples confirm that these database may be a novel tool for CEIP to assess a potential abuse of a medication.

Anti-Anxiety Agents↗